Yes, that is quite confusing, as everywhere in the SF source code there are references to POPCNT-enabled code via a <bool HasPopCnt> template.
But Tord is absolutely correct, I now see that the usage of the POPCNT routines has been disabled by default in bitcount.h (with a compiler conditional "USE_POPCNT"). To obtain the behaviour I described, you need to compile with the "USE_POPCNT" conditional on.
Interestingly Tord's estimate of about 3% speed improvement confirms my findings with Houdini, basically the POPCNT versions are hardly worth the while.
Robert
Rybka 4 vs Stockfish 1.8 - Long TC Match - LIVE BROADCAST!
- Robert Houdart
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Re: Rybka 4 vs Stockfish 1.8 - Long TC Match - LIVE BROADCAS
Well, if one has a CPU which supports SSE 4.2 then it's very little effort from the end-user point of view (me). But I can see that it's not always easy to compile this stuff.Robert Houdart wrote:Yes, that is quite confusing, as everywhere in the SF source code there are references to POPCNT-enabled code via a <bool HasPopCnt> template.
But Tord is absolutely correct, I now see that the usage of the POPCNT routines has been disabled by default in bitcount.h (with a compiler conditional "USE_POPCNT"). To obtain the behaviour I described, you need to compile with the "USE_POPCNT" conditional on.
Interestingly Tord's estimate of about 3% speed improvement confirms my findings with Houdini, basically the POPCNT versions are hardly worth the while.
Robert
Robert, hopefully you will show up on chessbomb.com for the chat. I think many people would like to see you there.
Right now in Game #1 Houdini is under pressure.
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Re: Rybka 4 vs Stockfish 1.8 - Long TC Match - LIVE BROADCAS
Robert,
This is a quote from Tord during game #1 when Houdini uses tons of time in forced mate positions:
Might not be the coolest feature, but it's handy when it comes to games like this one.
Best Regards,
Martin
This is a quote from Tord during game #1 when Houdini uses tons of time in forced mate positions:
Is this something you can implement?TordRomstad: It would have been over a lot sooner if Houdini had played instantly when there's a forced mate, as most engines do.
Might not be the coolest feature, but it's handy when it comes to games like this one.
Best Regards,
Martin
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Re: Rybka 4 vs Stockfish 1.8 - Long TC Match - LIVE BROADCAS
A very nice attack by SF in the first game - I find king safety by far the most difficult component to improve, as this game demonstrates .Martin Thoresen wrote:Robert,
This is a quote from Tord during game #1 when Houdini uses tons of time in forced mate positions:
Is this something you can implement?TordRomstad: It would have been over a lot sooner if Houdini had played instantly when there's a forced mate, as most engines do.
Might not be the coolest feature, but it's handy when it comes to games like this one.
Best Regards,
Martin
I'll take a look at the time usage when there's a forced mate, but why didn't the GUI stop the game around move 40 when both programs were already announcing mate scores ?
Robert