From: Marco Costalba <mcostalba@gmail.com>
Date: Mon, 22 Nov 2010 17:40:36 +0000 (+0100)
Subject: Fix 'generation' type to uint8_t
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=200fc56e9ce2ce5b879b0cae8268703f041c40b2

Fix 'generation' type to uint8_t

When we store this value in TT we cut this to 9 bits,
so we need a smaller variable otherwise comparisons
like:

   replace->generation() == generation

Are always false if generation is bigger then the maximum
TT storable value.

This fixes a very nasty and difficult to spot bug (2 weeks for
regression hunting).

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---

diff --git a/src/movepick.cpp b/src/movepick.cpp
index 264d941f..2e8eb665 100644
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -51,10 +51,10 @@ namespace {
   };
 
   CACHE_LINE_ALIGNMENT
-  const int MainSearchPhaseTable[] = { PH_TT_MOVES, PH_GOOD_CAPTURES, PH_KILLERS, PH_NONCAPTURES, PH_BAD_CAPTURES, PH_STOP};
-  const int EvasionsPhaseTable[] = { PH_TT_MOVES, PH_EVASIONS, PH_STOP};
-  const int QsearchWithChecksPhaseTable[] = { PH_TT_MOVES, PH_QCAPTURES, PH_QCHECKS, PH_STOP};
-  const int QsearchWithoutChecksPhaseTable[] = { PH_TT_MOVES, PH_QCAPTURES, PH_STOP};
+  const uint8_t MainSearchPhaseTable[] = { PH_TT_MOVES, PH_GOOD_CAPTURES, PH_KILLERS, PH_NONCAPTURES, PH_BAD_CAPTURES, PH_STOP};
+  const uint8_t EvasionsPhaseTable[] = { PH_TT_MOVES, PH_EVASIONS, PH_STOP};
+  const uint8_t QsearchWithChecksPhaseTable[] = { PH_TT_MOVES, PH_QCAPTURES, PH_QCHECKS, PH_STOP};
+  const uint8_t QsearchWithoutChecksPhaseTable[] = { PH_TT_MOVES, PH_QCAPTURES, PH_STOP};
 }
 
 
diff --git a/src/movepick.h b/src/movepick.h
index c656deaf..c71ff1a9 100644
--- a/src/movepick.h
+++ b/src/movepick.h
@@ -64,7 +64,7 @@ private:
   Bitboard pinned;
   MoveStack ttMoves[2], killers[2];
   int badCaptureThreshold, phase;
-  const int* phasePtr;
+  const uint8_t* phasePtr;
   MoveStack *curMove, *lastMove, *lastGoodNonCapture, *badCaptures;
   MoveStack moves[MOVES_MAX];
 };
diff --git a/src/tt.h b/src/tt.h
index ff1cb910..ee10b3f0 100644
--- a/src/tt.h
+++ b/src/tt.h
@@ -120,7 +120,7 @@ public:
 private:
   size_t size;
   TTCluster* entries;
-  int generation;
+  uint8_t generation; // To properly compare, size must be smaller then TT stored value
 };
 
 extern TranspositionTable TT;