Small cleanups

Delete cast to int in movepick.
update AUTHORS.
adjust assert in sigmoid.
fix spelling mistakes in README

closes https://github.com/official-stockfish/Stockfish/pull/3922
closes https://github.com/official-stockfish/Stockfish/pull/3948
closes https://github.com/official-stockfish/Stockfish/pull/3942

No functional change

diff --git a/AUTHORS b/AUTHORS
index 65620886dcd7cc901590583fd3fc58dfb28443ff..34b95ba5380126bee3906f18e4436514c8170310 100644 (file)
--- a/AUTHORS
+++ b/AUTHORS
@@ -155,6 +155,7 @@ Pascal Romaret
 Pasquale Pigazzini (ppigazzini)
 Patrick Jansen (mibere)
 pellanda
+Peter Schneider (pschneider1968)
 Peter Zsifkovits (CoffeeOne)
 Praveen Kumar Tummala (praveentml)
 Rahul Dsilva (silversolver1)

diff --git a/README.md b/README.md
index 330d19edd1f666ca90296fe0cdabe83b27e2c230..37dae511f073a3031810e00eee1aedb6b01ce839 100644 (file)
--- a/README.md
+++ b/README.md
@@ -10,12 +10,11 @@ Cute Chess, eboard, Arena, Sigma Chess, Shredder, Chess Partner or Fritz) in ord
 to be used comfortably. Read the documentation for your GUI of choice for information
 about how to use Stockfish with it.
 
-The Stockfish engine features two evaluation functions for chess, the classical
-evaluation based on handcrafted terms, and the NNUE evaluation based on efficiently
-updatable neural networks. The classical evaluation runs efficiently on almost all
-CPU architectures, while the NNUE evaluation benefits from the vector
-intrinsics available on most CPUs (sse2, avx2, neon, or similar).
-
+The Stockfish engine features two evaluation functions for chess.
+The efficiently updatable neural network (NNUE) based evaluation is the default and by far the strongest.
+The classical evaluation based on handcrafted terms remains available.
+The strongest network is integrated in the binary and downloaded automatically during the build process.
+The NNUE evaluation benefits from the vector intrinsics available on most CPUs (sse2, avx2, neon, or similar).
 
 ## Files
 
@@ -37,7 +36,7 @@ This distribution of Stockfish consists of the following files:
 
 The Universal Chess Interface (UCI) is a standard protocol used to communicate with
 a chess engine, and is the recommended way to do so for typical graphical user interfaces
-(GUI) or chess tools. Stockfish implements the majority of it options as described
+(GUI) or chess tools. Stockfish implements the majority of its options as described
 in [the UCI protocol](https://www.shredderchess.com/download/div/uci.zip).
 
 Developers can see the default values for UCI options available in Stockfish by typing
@@ -103,7 +102,7 @@ change them via a chess GUI. This is a list of available UCI options in Stockfis
     Example: `C:\tablebases\wdl345;C:\tablebases\wdl6;D:\tablebases\dtz345;D:\tablebases\dtz6`
 
     It is recommended to store .rtbw files on an SSD. There is no loss in storing
-    the .rtbz files on a regular HD. It is recommended to verify all md5 checksums
+    the .rtbz files on a regular HDD. It is recommended to verify all md5 checksums
     of the downloaded tablebase files (`md5sum -c checksum.md5`) as corruption will
     lead to engine crashes.
 
@@ -322,10 +321,10 @@ it (either by itself or as part of some bigger software package), or
 using it as the starting point for a software project of your own.
 
 The only real limitation is that whenever you distribute Stockfish in
-some way, you MUST always include the full source code, or a pointer
+some way, you MUST always include the license, the full source code, or a pointer
 to where the source code can be found, to generate the exact binary
 you are distributing. If you make any changes to the source code,
-these changes must also be made available under the GPL.
+these changes must also be made available under the GPL v3.
 
 For full details, read the copy of the GPL v3 found in the file named
 [*Copying.txt*](https://github.com/official-stockfish/Stockfish/blob/master/Copying.txt).

diff --git a/src/misc.h b/src/misc.h
index b962673384b97e2c9660cfd6e2aeee122ea385cd..b666b6be45be9c41a977af40d04c2e3493926a30 100644 (file)
--- a/src/misc.h
+++ b/src/misc.h
@@ -163,7 +163,7 @@ inline int64_t sigmoid(int64_t t, int64_t x0,
                                   int64_t  P,
                                   int64_t  Q)
 {
-   assert(C > 0);
+   assert(C > 0 && Q != 0);
    return y0 + P * (t-x0) / (Q * (std::abs(t-x0) + C)) ;
 }
 

diff --git a/src/movepick.cpp b/src/movepick.cpp
index dc35113f90e6d0bad4f857e35cc0fd853f2b6cdf..c948620b5551a6b05436fe45c2e4c3a01c26f7e9 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -107,8 +107,8 @@ void MovePicker::score() {
 
   for (auto& m : *this)
       if constexpr (Type == CAPTURES)
-          m.value =  int(PieceValue[MG][pos.piece_on(to_sq(m))]) * 6
-                   + (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))];
+          m.value = 6 * PieceValue[MG][pos.piece_on(to_sq(m))]
+                   +    (*captureHistory)[pos.moved_piece(m)][to_sq(m)][type_of(pos.piece_on(to_sq(m)))];
 
       else if constexpr (Type == QUIETS)
           m.value =      (*mainHistory)[pos.side_to_move()][from_to(m)]