--- Comment #14 from Manu <turkey...@gmail.com> 2012-05-02 13:06:19 PDT ---
(In reply to comment #13)
> (In reply to comment #12)
> > (In reply to comment #11)
> > > Haven't done the special case optimizations for constant loading.
> > No problem, I'm using GDC anyway which might detect those in the back end.
> > An efficient implementation would certainly use at least an xor for 0
> > initialisation, and the other tricks will get different mileage depending on
> > the length of the pipeline surrounding. Not accessing memory is always
> > better
> > if there are pipeline cycles to soak up the latency.
> The -1 trick is always worth doing, I think. Agner Fog has a nice list in his
> optimisation manuals, but the only ones _always_ worth doing are the 0 and -1
> integer cases, and the 0.0 floating point case (also using xor).
If the compiler knows anything about the pipeline around the code, it should be
able to make the best choice about the others.
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------