[llvm-commits] [PATCH][Fastmath, Instcombine] Enhancement of Fdiv

[dag at cray.com]

Eli Friedman <eli.friedman at gmail.com> writes:

>> Every single one of these transformations can change fp arithmetic
>> answers and thus we must have a way to disable them on the command line.
>
> We're only doing these transformations for instructions marked "fast"
> (http://llvm.org/docs/LangRef.html#fast-math-flags), i.e. compiled
> with -ffast-math .  Giving each individual transform a flag seems like
> way more detail than is actually useful.

That's not what I meant.  The "fast" solution is exactly what I was
looking for.  I didn't know about that.  Thanks!

                                    -David