[PATCH] D156506: [clang][Interp] Check floating results for NaNs

[Joshua Cranmer via Phabricator via cfe-commits]

jcranmer-intel added a comment.

You definitely don't want these rules to apply to all qNaNs. It's when an input operand is an sNaN for many operations. Note that the result of an operation with an sNaN as input (and FP result type) is a qNaN output, and the only times that you get an sNaN output are the times when you never signal (I think), so checking the result type is incorrect.



================
Comment at: clang/lib/AST/Interp/Interp.cpp:534-539
   if ((Status & APFloat::opStatus::opInvalidOp) &&
       FPO.getExceptionMode() != LangOptions::FPE_Ignore) {
     // There is no usefully definable result.
     S.FFDiag(E);
     return false;
   }
----------------
A further note is that sNaNs signal `FE_INVALID` when used, so sNaN should generally fall into this if statement in particular.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D156506/new/

https://reviews.llvm.org/D156506