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Don't read eval from TT anymore 

Rely fully on eval cache. Note that we still save eval
info to TT, this is not needed at this moment and will be
removed in future patches. We keep it so to have a "non
functional change" patch.

No functional change.
sf_3_base
Marco Costalba 2012-12-01 14:51:49 +01:00
parent 69de670353
commit a5ea3a202e
1 changed files with 13 additions and 34 deletions
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47
src/search.cpp
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@ -574,31 +574,21 @@ namespace {
// Step 5. Evaluate the position statically and update parent's gain statistics
if (inCheck)
ss->staticEval = ss->evalMargin = eval = VALUE_NONE;
else if (tte)
{
// Following asserts are valid only in single thread condition because
// TT access is always racy and its contents cannot be trusted.
assert(tte->static_value() != VALUE_NONE || Threads.size() > 1);
assert(ttValue != VALUE_NONE || tte->type() == BOUND_NONE || Threads.size() > 1);
ss->staticEval = eval = tte->static_value();
ss->evalMargin = tte->static_value_margin();
if (eval == VALUE_NONE || ss->evalMargin == VALUE_NONE) // Due to a race
eval = ss->staticEval = evaluate(pos, ss->evalMargin);
// Can ttValue be used as a better position evaluation?
if (ttValue != VALUE_NONE)
if ( ((tte->type() & BOUND_LOWER) && ttValue > eval)
|| ((tte->type() & BOUND_UPPER) && ttValue < eval))
eval = ttValue;
}
else
{
eval = ss->staticEval = evaluate(pos, ss->evalMargin);
TT.store(posKey, VALUE_NONE, BOUND_NONE, DEPTH_NONE, MOVE_NONE,
ss->staticEval, ss->evalMargin);
// Can ttValue be used as a better position evaluation?
if (tte && ttValue != VALUE_NONE)
{
if ( ((tte->type() & BOUND_LOWER) && ttValue > eval)
|| ((tte->type() & BOUND_UPPER) && ttValue < eval))
eval = ttValue;
}
if (!tte)
TT.store(posKey, VALUE_NONE, BOUND_NONE, DEPTH_NONE, MOVE_NONE,
ss->staticEval, ss->evalMargin);
}
// Update gain for the parent non-capture move given the static position
@ -1151,18 +1141,7 @@ split_point_start: // At split points actual search starts from here
}
else
{
if (tte)
{
assert(tte->static_value() != VALUE_NONE || Threads.size() > 1);
ss->staticEval = bestValue = tte->static_value();
ss->evalMargin = tte->static_value_margin();
if (ss->staticEval == VALUE_NONE || ss->evalMargin == VALUE_NONE) // Due to a race
ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
}
else
ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
ss->staticEval = bestValue = evaluate(pos, ss->evalMargin);
// Stand pat. Return immediately if static value is at least beta
if (bestValue >= beta)