On Tuesday, 17 January 2023 at 23:08:19 UTC, Siarhei Siamashka
wrote:
On Tuesday, 17 January 2023 at 21:50:06 UTC, matheus wrote:
Question: Have you compared the timings between this way (With
ranges) and a normal way (Without ranges)?
If you are intensively using ranges, UFCS or the other
convenient high level language features, then the compiler
choice does matter a lot. And only LDC compiler is able to
produce fast binaries from such source code.
...
I ran in two sites: https://onecompiler.com/d and then
https://godbolt.org/, with the latter I set LDC with -O2.
My version (Source in the end) ran about 2x faster than the
version with ranges.
...
I'm using D Online Compiler from different platforms but
unfortunately I can't loop too much because they don't accept,
but anyway a normal version runs almost twice faster than this
version (With ranges).
Can you try to run the following diagnostics program on this D
Online Compiler platform?
https://gist.github.com/ssvb/5c926ed9bc755900fdaac3b71a0f7cfd
https://onecompiler.com/d/3yv7t9ap9
Gives me:
HelloWorld.d(43): Error: undefined identifier `volatileStore`
HelloWorld.d(44): Error: undefined identifier `volatileLoad`
If you like I could send or post here a version without ranges
to try out.
Please post it. This is interesting.
Like I said above I ran my version against the one with ranges
(From: https://github.com/quickfur/dcal/blob/master/dcal.d), and
I modified to just print the calendar for some year.
With godbolt.org LDC -O2 my version ran 2x faster, and here is
the source:
import std.stdio, std.string, std.conv, std.range, std.datetime;
import std.datetime.stopwatch : benchmark, StopWatch;
void draw_months(int year ,int month, int columns){
int i;
if(month>12){return;}
auto columspace = " ".replicate(columns);
write("\n");
for(i=0;i<columns;++i){
if(month+i>12){break;}
write(" " ~ " ".replicate(11*(i>0)) ~
columspace,capitalize(to!string(Date(year,month+i,1).month)));
}
write("\n");
auto m = new string[][](columns);
for(int j=0;j<columns;++j){
if(month+j>12){return;}
for(i=1;i<8;++i){
write(to!string(Date(1899,1,i).dayOfWeek)[0..2], " ");
}
int c = DW[to!string(Date(year,month+j,1).dayOfWeek)];
auto dm = Date(2023,month+j,1).daysInMonth;
for(i=0;i<c;++i){ m[j] ~= " "; }
for(i=1;i<dm+1;++i){ m[j] ~= i.to!string; }
for(;i<36;++i){ m[j] ~= " "; }
write(columspace);
}
//write("\n\n",m[0].length,"\n");
writeln();
for(int k=0;k<5;++k){
for(int j=0;j<columns;++j){
for(i=k*7;i<(k+1)*7;++i){
writef("%2s ",m[j][i]);
}
write(columspace);
}
writeln();
}
}
void draw_year(int year, int columns){
int steps = 12/columns;
for(int i=0;i<steps;++i){
draw_months(2023,(i*columns)+1,columns);
}
}
int[string] DW;
void main(){
int[string] dow;
int i, y = 2023, m = 1, d = 1;
auto sw = StopWatch();
sw.start();
for(i=1;i<8;++i){
DW[to!string(Date(1899,1,i).dayOfWeek)]=i-1;
}
for(i=0;i<10;++i){
draw_year(2023,3);
}
sw.stop();
writeln(sw.peek.total!"usecs");
}
Matheus.
