Reduce less for positions without tt move

Continuation of work on scaling.
In line with previous scaling patches this one massively reduces
reduction for moves that don't go thru lmr for position without a tt
move.

Passed VVLTC with STC bounds:
https://tests.stockfishchess.org/tests/view/679fd2450774dfd78deb12b2
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 74718 W: 19354 L: 19042 D: 36322
Ptnml(0-2): 5, 6724, 23595, 7024, 11

Passed VVLTC with LTC bounds:
https://tests.stockfishchess.org/tests/view/67a009930774dfd78deb2346
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 82638 W: 21587 L: 21212 D: 39839
Ptnml(0-2): 15, 7476, 25953, 7869, 6

closes https://github.com/official-stockfish/Stockfish/pull/5860

Bench: 2887850
This commit is contained in:
Michael Chaly
2025-02-04 22:14:13 +03:00
committed by Disservin
parent 67573218e1
commit e852d9880a

View File

@@ -1241,7 +1241,7 @@ moves_loop: // When in check, search starts here
{
// Increase reduction if ttMove is not present
if (!ttData.move)
r += 2117;
r += 1111;
// Note that if expected reduction is high, we reduce search depth here
value = -search<NonPV>(pos, ss + 1, -(alpha + 1), -alpha,