craig.topper added inline comments.
================ Comment at: clang/lib/AST/ExprConstant.cpp:9616 + return EvaluateFloat(E->getArg(0), Val, Info) && + Success(lround(Val.convertToDouble()), E); + } ---------------- zoecarver wrote: > lebedev.ri wrote: > > zoecarver wrote: > > > rsmith wrote: > > > > This assumes that the host `double` has the same behavior as the target > > > > `double`, which is not true in general. Generally the right thing to do > > > > is to implement the relevant functionality on `APFloat`, taking care to > > > > produce the right answer for the floating-point model being used by > > > > that `APFloat`. This also assumes that the host `long` is the same size > > > > as the target `long`, which again is not true in general. Finally, you > > > > need to catch the case where the `APFloat` does not fit into the target > > > > type; in that case, the best response is probably to treat the > > > > evaluation as non-constant and leave it to the runtime library to > > > > implement whatever error response it chooses. > > > I've updated it to do just that: if there is an error, it will treat this > > > evaluation as non-constant and leave it for the runtime library to > > > handle. > > > > > > How should I determine the width of the APInt? Because it is run at > > > compile-time, can I use the max size (long long)? Either way, how should > > > I get the correct size, maybe from a builtin long type? > > You probably want to look at the original callexpr, take it's return type, > > and look it up in typesystem (i'm not sure exactly how to do that here) > Ah, good idea. Will do. Info.Ctx.getIntWidth(E->getType()) I think. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D66862/new/ https://reviews.llvm.org/D66862 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
