[alberth]

I truly never understood why Apple deprecated Bitcode.

It was a super great idea because it allowed recompilation on the App Store to take advantage of new instructions.

[plorkyeran]

Bitcode did not allow recompilation to take advantage of new instructions. They dropped bitcode because they never actually managed to do anything with it other than the armvk7 to arm64_32 recompilation, and that required specifically designing arm64_32 around what was possible with bitcode.

Updating apps to use new vector instructions is far more complicated than upgrading to a new compiler version and having it magically get faster.

[sgerenser]

SME is very specialized, right now no compiler (that I know of) is really able to take general-purpose code and output optimized SME. So for these instructions at least, bitcode wouldn’t be of any benefit.

[astrange]

Autovectorization doesn't work without extreme levels of handholding, so the optimization idea was basically a myth.