X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fvalue.h;h=4b62027267847592c63ef4a50895dc5b292625e4;hp=d54f81961174472cc7d8fde5b624ef18d3b9abde;hb=06a350f1aee97f05c3416853fb54385b23030ebc;hpb=ba07b95ee09896a5835d44f2086b92dde2091b3d

diff --git a/src/value.h b/src/value.h
index d54f8196..4b620272 100644
--- a/src/value.h
+++ b/src/value.h
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2009 Marco Costalba
+  Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -33,13 +33,16 @@
 ////
 
 enum ValueType {
-  VALUE_TYPE_NONE = 0,
+  VALUE_TYPE_NONE =  0,
   VALUE_TYPE_UPPER = 1,  // Upper bound
   VALUE_TYPE_LOWER = 2,  // Lower bound
   VALUE_TYPE_EXACT = 3,  // Exact score
-  VALUE_TYPE_EVAL  = 4,  // Evaluation cache
-  VALUE_TYPE_EV_UP = 5,  // Evaluation cache for upper bound
-  VALUE_TYPE_EV_LO = 6   // Evaluation cache for lower bound
+  VALUE_TYPE_EVAL  = 4,  // Static evaluation value
+  VALUE_TYPE_NULL  = 8,  // Null search value
+
+  VALUE_TYPE_EV_UP = VALUE_TYPE_EVAL | VALUE_TYPE_UPPER,
+  VALUE_TYPE_EV_LO = VALUE_TYPE_EVAL | VALUE_TYPE_LOWER,
+  VALUE_TYPE_NS_LO = VALUE_TYPE_NULL | VALUE_TYPE_LOWER,
 };
 
 
@@ -48,7 +51,8 @@ enum Value {
   VALUE_KNOWN_WIN = 15000,
   VALUE_MATE = 30000,
   VALUE_INFINITE = 30001,
-  VALUE_NONE = 30002
+  VALUE_NONE = 30002,
+  VALUE_ENSURE_SIGNED = -1
 };
 
 
@@ -56,10 +60,22 @@ enum Value {
 /// integer (enum), first LSB 16 bits are used to store endgame
 /// value, while upper bits are used for midgame value.
 
-enum Score {};
+// Compiler is free to choose the enum type as long as can keep
+// its data, so ensure Score to be an integer type.
+enum Score { ENSURE_32_BITS_SIZE_P = (1 << 16), ENSURE_32_BITS_SIZE_N = -(1 << 16)};
+
+// Extracting the _signed_ lower and upper 16 bits it not so trivial
+// because according to the standard a simple cast to short is
+// implementation defined and so is a right shift of a signed integer.
+inline Value mg_value(Score s) { return Value(((int(s) + 32768) & ~0xffff) / 0x10000); }
 
+// Unfortunatly on Intel 64 bit we have a small speed regression, so use a faster code in
+// this case, although not 100% standard compliant it seems to work for Intel and MSVC.
+#if defined(IS_64BIT) && (!defined(__GNUC__) || defined(__INTEL_COMPILER))
 inline Value eg_value(Score s) { return Value(int16_t(s & 0xffff)); }
-inline Value mg_value(Score s) { return Value((int(s) + 32768) >> 16); }
+#else
+inline Value eg_value(Score s) { return Value((int)(unsigned(s) & 0x7fffu) - (int)(unsigned(s) & 0x8000u)); }
+#endif
 
 inline Score make_score(int mg, int eg) { return Score((mg << 16) + eg); }