On Tuesday, 2 October 2012 at 22:13:10 UTC, Timon Gehr wrote:
On 10/03/2012 12:11 AM, Timon Gehr wrote:
...
$ cat ixidbench.d
module main;
import std.stdio, std.algorithm, std.range, std.datetime;
enum MAX = 10_000_000_000UL;
void main() {
StopWatch sw;
sw.start;
auto sum1 = MAX.iota.map!(x => x * x).reduce!"a + b";
sw.stop;
sw.peek.msecs.writeln("msecs");
sum1.writeln;
sw.reset;
sw.start;
ulong sum2 = 0;
foreach(i;0..MAX)
sum2 += i * i;
sw.stop;
sw.peek.msecs.writeln("msecs");
sum2.writeln;
}
$ ldmd2 -O -release -inline ixidbench.d -ofixidbench
$ ./ixidbench
6528msecs
7032546979563742720
7518msecs
7032546979563742720
$ gdmd -O -release -inline ixidbench.d -ofixidbench
$ ./ixidbench
11250msecs
7032546979563742720
11233msecs
7032546979563742720
Yes, I think it was just the compiler and compiler options rather
than anything inherent in the method, DMD produced much slower
code than GDC for the functional version. It's interesting that
it's significantly faster in the functional style with LDC.
