From 95af1e28beb5257b26d1271e4c93e471f0f3c9f8 Mon Sep 17 00:00:00 2001
From: Marco Costalba <mcostalba@gmail.com>
Date: Thu, 20 Aug 2009 16:30:34 +0100
Subject: [PATCH] Fix some asserts raised by is_ok()

There were two asserts.

The first was raised because is_ok() was called at the
beginning of do_castle_move() and this is wrong after
the last code reformatting because at that point the state
is already modified by the caller do_move().

The second, raised by debugIncrementalEval, was due to a
rounding error in compute_value() that occurs because
TempoValueEndgame was updated in an odd number by patch

"Merge Joona Kiiski evaluation tweaks" (3ed603cd) of 13/3/2009

This line in compute_value() is the guilty one:

result += (side_to_move() == WHITE)? TempoValue / 2 : -TempoValue / 2;

The fix is to increment TempoValueEndgame so to be even.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
---
 src/position.cpp | 9 ++++++++-
 src/value.h      | 2 +-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/position.cpp b/src/position.cpp
index d37d35b4..c5d05798 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -886,6 +886,8 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) {
 
   st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame;
   st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame;
+
+  assert(is_ok());
 }
 
 
@@ -953,7 +955,6 @@ void Position::do_capture_move(Bitboard& key, PieceType capture, Color them, Squ
 
 void Position::do_castle_move(Move m) {
 
-  assert(is_ok());
   assert(move_is_ok(m));
   assert(move_is_castle(m));
 
@@ -1042,6 +1043,8 @@ void Position::do_castle_move(Move m) {
 
   st->mgValue += (sideToMove == WHITE)? TempoValueMidgame : -TempoValueMidgame;
   st->egValue += (sideToMove == WHITE)? TempoValueEndgame : -TempoValueEndgame;
+
+  assert(is_ok());
 }
 
 
@@ -1146,6 +1149,8 @@ void Position::undo_move(Move m) {
 
   // Finally point our state pointer back to the previous state
   st = st->previous;
+
+  assert(is_ok());
 }
 
 
@@ -1210,6 +1215,8 @@ void Position::undo_castle_move(Move m) {
 
   // Finally point our state pointer back to the previous state
   st = st->previous;
+
+  assert(is_ok());
 }
 
 
diff --git a/src/value.h b/src/value.h
index cec4a439..51517462 100644
--- a/src/value.h
+++ b/src/value.h
@@ -96,7 +96,7 @@ const Value PieceValueEndgame[17] = {
 /// Bonus for having the side to move (modified by Joona Kiiski)
 
 const Value TempoValueMidgame = Value(48);
-const Value TempoValueEndgame = Value(21);
+const Value TempoValueEndgame = Value(22);
 
 
 ////
-- 
2.39.2