On Mon, Nov 07, 2016 at 08:26:01AM -0500, David Edelsohn wrote:
> On Mon, Nov 7, 2016 at 4:32 AM, Segher Boessenkool
> <seg...@kernel.crashing.org> wrote:
> > We transform floating point divide instructions to a faster series of
> > simple instructions, "swdiv". Currently we do not do that until the
> > first splitter pass, which is much too late for most optimisations
> > that can happen on those new instructions, e.g. the constant loads
> > are not CSEd inside an unrolled loop. This patch changes things so
> > those divide instructions are expanded during expand already.
> >
> > Bootstrapped and tested on powerpc64-linux; Bill has run SPEC on it,
> > and if anything it shows a slight improvement.
> >
> > Is this okay for trunk?
>
> Okay.
>
> But commenting on the ChangeLog entry is half the fun!
Okay :-)
2016-11-07 Segher Boessenkool <seg...@kernel.crashing.org>
* rs6000.md (div<mode>3): Expand using rs6000_emit_swdiv if
appropriate.
* vector.md (div<mode>3): Ditto.
Segher
