The reduction formula currently decreases by 1 if the move is a TT move.
This changes this by just setting the reduction to 0 instead.
Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 83136 W: 21145 L: 20758 D: 41233
Ptnml(0-2): 279, 9772, 21090, 10137, 290
https://tests.stockfishchess.org/tests/view/
653c0fbacc309ae839561584
Passed LTC:
LLR: 2.96 (-2.94,2.94) <0.50,2.50>
Total: 273150 W: 67987 L: 67171 D: 137992
Ptnml(0-2): 155, 30730, 73966, 31592, 132
https://tests.stockfishchess.org/tests/view/
653d9d02cc309ae839562fdf
closes https://github.com/official-stockfish/Stockfish/pull/4863
bench:
1110556
if ((ss + 1)->cutoffCnt > 3)
r++;
if ((ss + 1)->cutoffCnt > 3)
r++;
- // Decrease reduction for first generated move (ttMove)
+ // Set reduction to 0 for first generated move (ttMove)
+ // Nullifies all previous reduction adjustments to ttMove and leaves only history to do them
ss->statScore = 2 * thisThread->mainHistory[us][from_to(move)]
+ (*contHist[0])[movedPiece][to_sq(move)]
ss->statScore = 2 * thisThread->mainHistory[us][from_to(move)]
+ (*contHist[0])[movedPiece][to_sq(move)]