mibintc added inline comments.
================ Comment at: clang/lib/CodeGen/CGBuiltin.cpp:2844 + return RValue::get( + Builder.CreateArithmeticFence(ArgValue, ConvertType(ArgType))); + return RValue::get(ArgValue); ---------------- mibintc wrote: > kpn wrote: > > Does this say that the fence will be silently dropped if any of the fast > > math flags are disabled? Silently dropping something used for correctness > > makes me nervous. Is there a case where all of these flags are required for > > correct behavior of the fence? > Yes that is the idea, the clang builtin is only meaningful for float > operations when -ffast-math is enabled. If fast math isn't enabled then the > operations should already be performed strictly. I didn't have "isFast", > should rewrite with isFast to make it easier to understand Oops I'm wrong. @kbsmith1 tells me only the reassoc bit is interesting. i'll need to fix this in the documentation etc. Thanks for your careful reading. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D100118/new/ https://reviews.llvm.org/D100118 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
