[llvm] build_llvm_release.bat: add tarball export to x64 release (PR #79840)

[Benoît Amiaux via llvm-commits]

bamiaux wrote:

> Apologies for the delay, this got buried in my inbox.

No worries

> Thanks for sending the PR! People keep asking for this, so I think it's worth a try if people think it's useful.
> 
> I tried your patch and ended up with a 936 MB .tar.xz file :) Uncompressed it's 4.4 GB.

For reference clang+llvm-17.0.6-x86_64-linux-gnu-ubuntu-22.04.tar.xz is 951 MB which is in the same ball park

> .tar.xz is perhaps an unusual choice on Windows. On the other hand, a zip file would be much larger. I tried with 7zip's "maximum" setting and got a 1.34 GB file. (With "ultra" it's 1.33 GB so that doesn't seem worth it.) Do you think users would prefer a zip file even though it's a bit bigger?

I don't think it matters much, the file format is supported by 7z, and this tarball is primarily intended for developers.
If we change it, I'd prefer to have a 7z archive on windows & keep the file size as small as possible.



https://github.com/llvm/llvm-project/pull/79840