Oliver -- Sorry for the confusiong: Oliver Kullmann <O.Kullmann@xxxxxxxxxxxxx> writes: > On Sat, Aug 10, 2013 at 06:06:26PM -0600, Anthony Foiani wrote: > > They noticed that their earlier compiler (4.6.3 -O3) successfully > > reduced the loop, while 4.8.1 didn't. > For general enligthenment, could you quickly explain what "reduce > the loop" means? One can of course just get rid off the loop, > precomputing sum, That's exactly what I meant. Apologies for not knowing the correct phrasing. > which is, at least for me, an unexpected difference? (I would have > assumed that, if there is a difference, then Index=UInt should be > faster.) Seeing only a 15% difference, you probably want to run it multiple times and average out the values. Intuitively, I agree that the unsigned loop variable should be faster, but I have no idea what's actually going on behind the scenes there. Best regards, Anthony Foiani
