jhonnold / berserk

UCI Chess Engine written in C
GNU General Public License v3.0
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Utilize 128bit multiplication for TT indexing #440

Closed jhonnold closed 1 year ago

jhonnold commented 1 year ago

Bench: 4187168

12-byte entries (#437) introduced a problem where position hash values we're essentially limited to 48 bits. This mitigates the issue by utilizing the entire 64 bit hash in the TT indexing calculation.

STC

ELO   | 2.71 +- 3.27 (95%)
SPRT  | 10.0+0.10s Threads=1 Hash=8MB
LLR   | 2.97 (-2.94, 2.94) [-3.00, 0.00]
GAMES | N: 20624 W: 4990 L: 4829 D: 10805