I looked into doing this briefly, and a couple blockers were that I couldn't find any easy cloud services offering POWER that I could use for testing, the cheapest dev system I could find, the Talos II Development System, is itself $5000 once you add RAM and storage (https://www.raptorcs.com/content/TL2DS1/intro.html, they do have a cheaper system available in pre-order: https://www.raptorcs.com/content/TL1BC1/intro.html), and the C intrinsics that they offer work with special overloaded functions with a vector type extension to C, making it a lot harder to use the approach of just offering wrappers for basic intrinsics and then working on higher-level support on top of that.
I looked into doing this briefly, and a couple blockers were that I couldn't find any easy cloud services offering POWER that I could use for testing, the cheapest dev system I could find, the Talos II Development System, is itself $5000 once you add RAM and storage (https://www.raptorcs.com/content/TL2DS1/intro.html, they do have a cheaper system available in pre-order: https://www.raptorcs.com/content/TL1BC1/intro.html), and the C intrinsics that they offer work with special overloaded functions with a vector type extension to C, making it a lot harder to use the approach of just offering wrappers for basic intrinsics and then working on higher-level support on top of that.
Looks like gnzlbg put more effort into it, but ran into similar issues: https://github.com/rust-lang/rust/issues/42743#issuecomment-...