[PATCH] D93769: [clang] Add support for option -ffp-eval-method and extend #pragma float_control similarly

[Melanie Blower via Phabricator via cfe-commits]

mibintc added inline comments.


================
Comment at: clang/docs/LanguageExtensions.rst:3363
+
+When ``pragma float_control(source, off)`` or
+``pragma float_control(double, off)`` or
----------------
I'd like to add Intel ICL compatible syntax, but 'off' doesn't make too much sense to me. In the Intel compiler using'off' requires both ffp-exception-behavior to be ignore, and FENV_ACCESS to be off.  If that's true then setting float_control(source|double|extended, off) is allowable and the semantics of float evaluation method set to a 4th level "float eval fast" which is loosely described in the commentary as "don't care".  Ideally "float eval fast" would deliver the same results, in this context, as Microsoft's fp:fast command line option. I could make "off" an illegal setting, or warn that it's ignored. @andrew.w.kaylor  do you have any input here?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D93769/new/

https://reviews.llvm.org/D93769