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stockfish 1.8 - Eval hash gone?

Posted: Sun Jul 04, 2010 11:08 am
by edwardyu
I notice that stockfish 1.8 no longer has VALUE_TYPE_EVAL in tt (transposition table). Is Eval hash gone becuase it is no longer useful?

Re: stockfish 1.8 - Eval hash gone?

Posted: Sun Jul 04, 2010 11:31 am
by zamar
No. static value is now directly saved in TT. This saves some costly eval() calls and gives moderate speed-up

Re: stockfish 1.8 - Eval hash gone?

Posted: Sun Jul 04, 2010 12:31 pm
by edwardyu
zamar wrote:No. static value is now directly saved in TT. This saves some costly eval() calls and gives moderate speed-up
So the tte structure documentation is not updated? :-

Code: Select all

/// The TTEntry class is the class of transposition table entries
///
/// A TTEntry needs 96 bits to be stored
///
/// bit  0-31: key
/// bit 32-63: data
/// bit 64-79: value
/// bit 80-95: depth
///
/// the 32 bits of the data field are so defined
///
/// bit  0-16: move
/// bit 17-19: not used
/// bit 20-22: value type
/// bit 23-31: generation

Re: stockfish 1.8 - Eval hash gone?

Posted: Sun Jul 04, 2010 1:41 pm
by zamar
edwardyu wrote:
zamar wrote:No. static value is now directly saved in TT. This saves some costly eval() calls and gives moderate speed-up
So the tte structure documentation is not updated? :-
Yes, I forgot to update the documentation! Thanks for pointing this out :-)