zoecarver marked 2 inline comments as done. zoecarver added inline comments.
================ Comment at: clang/lib/AST/ExprConstant.cpp:9616 + return EvaluateFloat(E->getArg(0), Val, Info) && + Success(lround(Val.convertToDouble()), E); + } ---------------- 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. ================ Comment at: clang/test/SemaCXX/math-builtins.cpp:1 +// RUN: %clang_cc1 -std=c++11 %s + ---------------- lebedev.ri wrote: > -verify ? Yes, that worked. It was throwing me off the first time I tried because it doesn't expect the nan tests to error. Any ideas on generating a nan float? Thanks for the help :) 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
