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Revert storing of TT when returning from "stand pat"

After testing it seems patch is bad:

After 999 games 1+0: +242 -271 =486 -10 ELO

So restore saving of TT at the end but using new Joona
idea of storing as VALUE_TYPE_UPPER/VALUE_TYPE_LOWER instead
of VALUE_TYPE_EXACT.

Some optimization is still possible but better test new ideas
one by one.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
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1 parent 5a05814 commit dcdac83187f44b14893ea261abd647c829d32c2b @mcostalba committed Mar 27, 2009
Showing with 14 additions and 7 deletions.
  1. +14 −7 src/search.cpp
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21 src/search.cpp
@@ -1476,14 +1476,11 @@ namespace {
if (bestValue >= beta)
{
- // Update transposition table before to leave
- TT.store(pos, value_to_tt(bestValue, ply), depth, MOVE_NONE, VALUE_TYPE_EXACT);
- return bestValue;
- }
- else if (!isCheck && !tte && ei.futilityMargin == 0)
- {
// Store the score to avoid a future costly evaluation() call
- TT.store(pos, value_to_tt(bestValue, ply), Depth(-127*OnePly), MOVE_NONE, VALUE_TYPE_EVAL);
+ if (!isCheck && !tte && ei.futilityMargin == 0)
+ TT.store(pos, value_to_tt(bestValue, ply), Depth(-127*OnePly), MOVE_NONE, VALUE_TYPE_EVAL);
+
+ return bestValue;
}
if (bestValue > alpha)
@@ -1568,6 +1565,16 @@ namespace {
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
+ // Update transposition table
+ if (!pvNode)
+ {
+ Depth d = (depth == Depth(0) ? Depth(0) : Depth(-1));
+ if (bestValue < beta)
+ TT.store(pos, value_to_tt(bestValue, ply), d, MOVE_NONE, VALUE_TYPE_UPPER);
+ else
+ TT.store(pos, value_to_tt(bestValue, ply), d, MOVE_NONE, VALUE_TYPE_LOWER);
+ }
+
// Update killers only for good check moves
Move m = ss[ply].currentMove;
if (alpha >= beta && ok_to_history(pos, m)) // Only non capture moves are considered

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