Re: gdc or ldc for faster programs?
On Saturday, 29 January 2022 at 18:28:06 UTC, Ali Çehreli wrote: (And now we know gdc can go about 7% faster with additional command line switches.) No, we don't know this yet ;-) That's just what I said and I may be bullshitting. Or the configuration of my computer is significantly different from yours and the exact speedup/slowdown number may be different. So please verify it yourself. You can edit your `dub.json` file to add the following line to it: "dflags-gdc": ["-fno-weak-templates"], Then rebuild your spellout test program with gdc (just like you did before), run benchmarks and report results. The '-fno-weak-templates' option should show up in the gdc invocation command line.
Re: gdc or ldc for faster programs?
On Saturday, 29 January 2022 at 18:28:06 UTC, Ali Çehreli wrote: On 1/29/22 10:04, Salih Dincer wrote: > Could you also try the following code with the same configurations? The program you posted with 2 million random values: ldc 1.9 seconds gdc 2.3 seconds dmd 2.8 seconds I understand such short tests are not definitive but to have a rough idea between two programs, the last version of my program that used sprintf with 2 million numbers takes less time: ldc 0.4 seconds gdc 0.5 seconds dmd 0.5 seconds (And now we know gdc can go about 7% faster with additional command line switches.) Ali You need to be compiling with PGO to test the compilers optimizer to the maximum. Without PGO they have to assume a fairly conservative flow through the code which means things like inlining and register allocation are effectively flying blind.
Re: gdc or ldc for faster programs?
On 1/29/22 10:04, Salih Dincer wrote: > Could you also try the following code with the same configurations? The program you posted with 2 million random values: ldc 1.9 seconds gdc 2.3 seconds dmd 2.8 seconds I understand such short tests are not definitive but to have a rough idea between two programs, the last version of my program that used sprintf with 2 million numbers takes less time: ldc 0.4 seconds gdc 0.5 seconds dmd 0.5 seconds (And now we know gdc can go about 7% faster with additional command line switches.) Ali
Re: gdc or ldc for faster programs?
On Wednesday, 26 January 2022 at 18:00:41 UTC, Ali Çehreli wrote:
For completeness (and noise :/) here is the final version of
the program:
Could you also try the following code with the same
configurations?
```d
struct LongScale {
struct ShortStack {
short[] stack;
size_t index;
@property back() {
return this.stack[0];
}
@property push(short data) {
this.stack ~= data;
this.index++;
}
@property pop() {
return this.stack[--this.index];
}
}
ShortStack stack;
this(long i) {
long s, t = i;
for(long e = 3; e <= 18; e += 3) {
s = 10^^e;
stack.push = cast(short)((t % s) / (s/1000L));
t -= t % s;
}
stack.push = cast(short)(t / s);
}
string toString() {
string[] scale = [" zero", "thousand", "million",
"billion", "trillion", "quadrillion", "quintillion"];
string r;
for(long e = 6; e > 0; e--) {
auto t = stack.pop;
r ~= t > 1 ? " " ~to!string(t) : t ? " one" : "";
r ~= t ? " " ~scale[e] : "";
}
r ~= stack.back ? " " ~to!string(stack.back) : "";
return r.length ? r : scale[0];
}
}
import std.conv, std.stdio;
void main()
{
long[] inputs = [ 741, 1_500, 2_001,
5_005, 1_250_000, 3_000_042, 10_000_000,
1_000_000, 2_000_000, 100_000, 200_000,
10_000, 20_000, 1_000, 2_000, 74, 7, 0,
1_999_999_999_999];
foreach(long i; inputs) {
auto OUT = LongScale(i);
auto STR = OUT.toString[1..$];
writefln!"%s"(STR);
}
}
```
