fhahn added inline comments.
================ Comment at: clang/lib/Sema/SemaStmtAttr.cpp:144 + assert(ValueExpr && "Attribute must have a valid value expression."); + if (S.CheckLoopHintExpr(ValueExpr, St->getBeginLoc())) + return nullptr; ---------------- sdesmalen wrote: > david-arm wrote: > > fhahn wrote: > > > Is there a way to only accept `fixed_width/scalable` for targets that > > > support it? Not sure if we have enough information here, but we might be > > > able to reject it eg per target basis or something > > Hi @fhahn, I think if possible we'd prefer not to reject scalable vectors > > at this point. Theoretically there is no reason why we can't perform > > scalable vectorisation for targets that don't have hardware support for > > scalable vectors. In this case it simply means that vscale is 1. If you > > want we could add some kind of opt-remark in the vectoriser that says > > something like "target does not support scalable vectors, vectorising for > > vscale=1"? > I agree with @david-arm that we shouldn't prevent this in the front-end. Even > if the architecture may not support scalable vectors natively, there may > still be reasons to want to create scalable vectors in IR, for example to > have more portable IR. Hm, I am just a bit worried that it might be a bit confusing to users that do not know what scalable vectors are (it is obvious when knowing all about SVE, but I would assume most people don't necessarily know what this means). I guess that is not the biggest deal, as long `vectorize_width(X, scalable)` works for every target. > Even if the architecture may not support scalable vectors natively, there > may still be reasons to want to create scalable vectors in IR, for example to > have more portable IR. Sure, but there are so many other target-specific things encoded that make the IR really un-portable between targets. Granted, it is not impossible to convert IR between some architectures (as in arm64_32) CHANGES SINCE LAST ACTION https://reviews.llvm.org/D89031/new/ https://reviews.llvm.org/D89031 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
