HCha/Stockfish
1
0
Fork 0
mirror of https://github.com/HChaZZY/Stockfish.git synced 2025-12-21 01:27:16 +08:00
Code Issues Packages Projects Releases Wiki Activity

Fix: In qsearch do not use TT value when in a PV node

Browse Source 
We already do like this in search_pv(), so extend
also in qsearch().

Bug spotted by Joona Kiiski.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
Marco Costalba
2009-03-21 14:51:31 +01:00
parent 74160ac602
commit 16abc165d8
1 changed files with 8 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
src/search.cpp
View File

@@ -1417,10 +1417,14 @@ namespace {
if (pos.is_draw()) if (pos.is_draw())
return VALUE_DRAW; return VALUE_DRAW;
// Transposition table lookup // Transposition table lookup, only when not in PV
bool pvNode = (beta - alpha != 1);
if (!pvNode)
{
const TTEntry* tte = TT.retrieve(pos); const TTEntry* tte = TT.retrieve(pos);
if (tte && ok_to_use_TT(tte, depth, beta, ply)) if (tte && ok_to_use_TT(tte, depth, beta, ply))
return value_from_tt(tte->value(), ply); return value_from_tt(tte->value(), ply);
}
// Evaluate the position statically // Evaluate the position statically
EvalInfo ei; EvalInfo ei;
@@ -1443,7 +1447,6 @@ namespace {
// Initialize a MovePicker object for the current position, and prepare // Initialize a MovePicker object for the current position, and prepare
// to search the moves. Because the depth is <= 0 here, only captures, // to search the moves. Because the depth is <= 0 here, only captures,
// queen promotions and checks (only if depth == 0) will be generated. // queen promotions and checks (only if depth == 0) will be generated.
bool pvNode = (beta - alpha != 1);
MovePicker mp = MovePicker(pos, pvNode, MOVE_NONE, EmptySearchStack, depth, isCheck ? NULL : &ei); MovePicker mp = MovePicker(pos, pvNode, MOVE_NONE, EmptySearchStack, depth, isCheck ? NULL : &ei);
Move move; Move move;
int moveCount = 0; int moveCount = 0;