aaron.ballman added a subscriber: hubert.reinterpretcast. aaron.ballman added a comment.
In D136568#3880711 <https://reviews.llvm.org/D136568#3880711>, @jcranmer-intel wrote: > FWIW, I would be slightly wary of relying on cppreference as definitive for > niche semantic issues like this, although it is correct in this case. C2x is > actually pretty well-organized in Annex F, and enumerates most of the corner > cases specifically in every function. +1 to this point; the edge cases are pretty tricky and the standard is the source of truth for how we should be implementing this stuff. ================ Comment at: clang/lib/AST/ExprConstant.cpp:12452 + int Ilogb; + if (APFloat::opStatus St = ilogb(F, Ilogb); !isConstantOpStatus(St)) + return false; ---------------- jcranmer-intel wrote: > `long double` is `ppc_fp128` on at least some PPC targets, and while I'm not > entirely certain of what `ilogb` properly returns in the corner cases of the > `ppc_fp128`, I'm not entirely confident that the implementation of `APFloat` > is correct in those cases. I'd like someone with PPC background to comment in > here. Paging @hubert.reinterpretcast for help finding a good person to comment on the PPC questions. ================ Comment at: llvm/include/llvm/ADT/APFloat.h:450-454 /// For special APFloat values, this returns special error codes: /// /// NaN -> \c IEK_NaN /// 0 -> \c IEK_Zero /// Inf -> \c IEK_Inf ---------------- Is this part of the comment still accurate? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D136568/new/ https://reviews.llvm.org/D136568 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
