On Sun, Jun 24, 2012 at 10:24 PM, Hugh Fisher <[email protected]> wrote: > AFAIK it won't be possible to use predication for this unless > every math instruction has two variants, one which sets the > condition codes and one which doesn't.
In this case it would certainly be more efficient to use a branch. I'm not sure it would be wise to predicate out a long string of instructions. However, I have decided to borrow from SPARC the idea of having a "write flags" bit. At the moment, I'm putting it into the instruction, but alternatively, we could make it a flag that is turned on/off by an instruction. > > Predicated (conditional) move instructions would be very handy > though, as there are a lot of min/max/clamp operations in GPU > graphics code. Most definitely. CMOVE, MUX, MIN, MAX, etc. Oh, and clamp. Gotta add that. -- Timothy Normand Miller http://www.cse.ohio-state.edu/~millerti Open Graphics Project _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
