New version: Demolito 2017-08-26

[Dann Corbit]

Hi Dann,

Sensational!
Lesser as Thinker?
Do you know how many Senpai have?

Best
Frank

Senpai has 7359 Lines.

I think Senpai is beautiful, and I love the name too, but it is not being actively developed.

[Frank Quisinsky]

Hi Dann,

but I am sure Fabien have a 400 Elo stronger version as Senpai and have fun with computer chess and the development of Senpai. Fabien is full of great ideas and have a lot of energy if I remember on all the mails I got from him.

But the topic is Demolito!

My thanks to Lucas.
Great work by Lucas, the next Genius, the computer chess community have (opinion by many persons I have contacts).
Have not many knowlege about programming.

The playing strenght is sensational for the very small code.
This is fact!!

A computer chess HIGHLIGHT 2017!
Fact too!!

Best
Frank

I will added the information in my engine overview and will test after FEOBOS the engine. To many work at the moment. But I am very happy for the moment to have it.

A small strong code is optimal for chess computers.
Loud thinking ... chess computer will get more attention the next years, sure here. Means, the good and old chess computers.

[Guenther]

About 50-60 elo gain in my testing: self-play, tc=8"+0.08", high resolution book (5 plies). As usual, expect elo compression in rating lists, due to higher TC and longer book lines.

http://open-chess.org/viewtopic.php?f=7 ... 534#p23534

Source code on github: https://github.com/lucasart/demolito.

A compile for 'old' machines would be nice again.

Guenther

[Ras]

Incredible, so little code and so strong. With this line count, I barely get my opening book compiler done.

Plus that the code is really nice to look at, well structured and maintainable.

Btw., CppCheck shows one issue (apart from style stuff). In smp_resize(), Workers is nulled upon realloc failure, but not freed.

[Ras]

A small strong code is optimal for chess computers.

Won't happen with dedicated units. Demolito has little code, but the static RAM usage alone is about 1 MB, and that is not counting stack and hash tables. Reason is the bitboards, mostly for rooks and bishops. Even the new Millennium Chess Genius Exclusive has "only" 384k of on-chip RAM.

Of course, with units like DGT Pi or Revelation, that's not a problem because in fact, they are small Linux machines. That's why they can run Stockfish. Once you have Linux onboard, you need to put in external RAM anyway.

[Dann Corbit]

A small strong code is optimal for chess computers.

Won't happen with dedicated units. Demolito has little code, but the static RAM usage alone is about 1 MB, and that is not counting stack and hash tables. Reason is the bitboards, mostly for rooks and bishops. Even the new Millennium Chess Genius Exclusive has "only" 384k of on-chip RAM.

Of course, with units like DGT Pi or Revelation, that's not a problem because in fact, they are small Linux machines. That's why they can run Stockfish. Once you have Linux onboard, you need to put in external RAM anyway.

Stockfish runs on every phone I have tried (I get the droidfish version).

[Ras]

Stockfish runs on every phone I have tried (I get the droidfish version).

Smartphones have 1 or 2 GB of RAM and a full-fledged OS. In fact, they are small PCs.

The dedicated units Frank is referring to have around a thousand times less RAM because they are Cortex-M based, not Cortex-A like smartphones. Plus that depending on the chip, the RAM is not even a continuous area. On the upside, you also get around 512k - 2MB of flash ROM for code and constant data.

The issue is that the bitboards are not constant data, so you need to link them into a RAM section, and with 1 MB of bitboards, there is no way to get that running in dedicated units (except those that are small Linux machines in a chessboard). Therefore, even the new Millennium Chess Genius Exclusive is not capable of running a Demolito port.

[mar]

Plus that the code is really nice to look at, well structured and maintainable.

Demolito has the cleanest code base I ever saw in a chess engine.

[Ras]

Demolito has the cleanest code base I ever saw in a chess engine.

My favourite is the use of setjmp/longjmp. That is goto on steroids and allows for ultimate dirty hacks. The amazing thing is that this actually is exception handling in plain C in a way that even improves the structure. I've never seen anything like this in an application, i.e. outside of low-level system programming.

[Dann Corbit]

Plus that the code is really nice to look at, well structured and maintainable.

Demolito has the cleanest code base I ever saw in a chess engine.

Too bad Bas Hamstra's code for Tao was never public.
It was really beautiful.