rsandifo-arm wrote: > However we choose to emit this particular builtin, should we provide a way to > write a function like this? Like, the caller has to either support sve, or > have streaming enabled. Maybe call it __arm_streaming_compatible_requires_sve.
I'd like to make two (probably obvious) points before answering this: * The existing three-way choice between normal, `__arm_streaming`, and `__arm_streaming_compatible` is simply a choice between possible incoming and outgoing PSTATE.SM states at runtime (0, 1, and 0 or 1, respectively). It's intended to be independent of the architecture level, except for the fact that using `__arm_streaming` is an error when SME is not enabled. * If `__arm_streaming_compatible` is being used to write a vector routine, the question isn't likely to be just “do I have SVE?” but “do I have this particular set of SVE features”? For example, I imagine many integer-based algorithms would want at least SVE2. At some point SVE2p1 would become a baseline for some users. So if someone wants to say both “this function should be streaming-compatible” and “this function assumes it has access to these streaming SVE features” then I think those things should be specified as two separate annotations, rather than a single combined one. The second one (about assuming/requiring available features) is useful more generally, for non-streaming and `__arm_streaming` as well as `__arm_streaming_compatible`. https://github.com/llvm/llvm-project/pull/92427 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
