On Friday, June 17, 2016 at 4:48:06 PM UTC+2, gordo...@gmail.com wrote: > > I don't see the point to the exercise as far as optimizing golang is > concerned.
It is a general rule that using more registers results in faster code. > Your experiment just shows that Your compiler (GCC?) My post containing the example mentions that the compiler is clang 3.9. > missed an optimization as far as reducing backend latency goes. > It is significant because it indicates that the clang compiler might be completely missing the general rule which I mentioned above. You may also find that swapping the order of some of the instructions such > as the second and the third in the loop may also reduce backend latency > further. > Swapping the order of instruction in the example results in the same or lower performance. I am not on a high end Intel CPU now, but when I was I found that with a > buffer size adjusted to the L1 cache size (8192 32-bit words or 32 > Kilobytes) that eratspeed ran on an Intel 2700K @ 3.5 GHz at about 3.5 > clock cycles per loop (about 405,000,000 loops for this range). > > My current AMD Bulldozer CPU has a severe cache bottleneck and can't come > close to this speed by a factor of about two. Which Bulldozer version do you have: original Bulldozer, Piledriver, Steamroller/Kaveri or Excavator/Carrizo? -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
