From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Wed, 6 Oct 2021 17:16:02 +0000 (+0200)
Subject: Compute ttCapture earlier
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=580698e5e57f40dcba52b92a7f0c7a0e9ab09437

Compute ttCapture earlier

Compute ttCapture earlier, and reuse.

passed STC:
LLR: 2.93 (-2.94,2.94) <-2.50,0.50>
Total: 74128 W: 18640 L: 18578 D: 36910
Ptnml(0-2): 224, 7970, 20649, 7962, 259
https://tests.stockfishchess.org/tests/view/615dd9fa1a32f4036ac7fc4d

closes https://github.com/official-stockfish/Stockfish/pull/3734

No functional change
---

diff --git a/src/search.cpp b/src/search.cpp
index bdd139ce..1aaf53d8 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -658,6 +658,7 @@ namespace {
     ttValue = ss->ttHit ? value_from_tt(tte->value(), ss->ply, pos.rule50_count()) : VALUE_NONE;
     ttMove =  rootNode ? thisThread->rootMoves[thisThread->pvIdx].pv[0]
             : ss->ttHit    ? tte->move() : MOVE_NONE;
+    ttCapture = ttMove && pos.capture_or_promotion(ttMove);
     if (!excludedMove)
         ss->ttPv = PvNode || (ss->ttHit && tte->is_pv());
 
@@ -683,7 +684,7 @@ namespace {
             if (ttValue >= beta)
             {
                 // Bonus for a quiet ttMove that fails high
-                if (!pos.capture_or_promotion(ttMove))
+                if (!ttCapture)
                     update_quiet_stats(pos, ss, ttMove, stat_bonus(depth), depth);
 
                 // Extra penalty for early quiet moves of the previous ply
@@ -691,7 +692,7 @@ namespace {
                     update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, -stat_bonus(depth + 1));
             }
             // Penalty for a quiet ttMove that fails low
-            else if (!pos.capture_or_promotion(ttMove))
+            else if (!ttCapture)
             {
                 int penalty = -stat_bonus(depth);
                 thisThread->mainHistory[us][from_to(ttMove)] << penalty;
@@ -948,7 +949,6 @@ namespace {
 
 moves_loop: // When in check, search starts here
 
-    ttCapture = ttMove && pos.capture_or_promotion(ttMove);
     int rangeReduction = 0;
 
     // Step 11. A small Probcut idea, when we are in check