On Mon, 19 Mar 2007, Shawn O. Pearce wrote: > > DrNick suggested on #git to try flipping the isspace test around. > This is a smaller change and generated the same ~3.60 seconds run > as Dscho's patch. I like DrNick's version better. ;-) For me, the result seems to be in the noise. It may be due to running on Core 2. It's not very sensitive to micro-optimizations like this. It definitely makes sense to test the *stable* test first, since that will help branch prediction (the "isspace()" test is *not* very predictable), so I don't disagree with the patch, but I suspect it depends a lot on the microarchitecture just how much it matters. Do you perhaps have a P4? It has a very bad branch mispredict penalty, so putting the predictable branch first could explain the big difference you see.. Dscho's bigger patch probably helps more on an in-order architecture, and should be equally good on a P4 (or Opteron). On Core 2, neither of the patches seem to make a huge difference. Linus - To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html