Matrix mul

[Sergey Gromov]

Sat, 22 Nov 2008 20:14:37 -0500, bearophile wrote:

> Can you or someone else run that little D code, so you can tell me if
> my timings are right?

Tested your code using DMD 2.019.  You are right.  The #1 is about 30
times slower than #2: 10s against 0,3s on my laptop.  I've also tried to
replace CRT malloc with GC malloc in #2 and it ran just a bit slower--I
would say around 4%--even though I didn't call hasNoPointers() anywhere.

The really weird part is, if I comment out the "init mats randomly" loop
in #1, it becomes twice as slow, i.e. 20s against the original 10s.  I
don't get it.