move-do: use castling flags, other improvements (~12% on perft)

- always set K square and castling flags (remove expensive tests on K and castling flags)
- simplify castling rook move
- more restrictive sq_castle[]

Makefile

@@ -39,7 +39,9 @@ OBJ       := $(addprefix $(OBJDIR)/,$(SRC_FN:.c=.o))
 TSTSRC    := $(wildcard $(TSTDIR)/*.c)
 
 LIB       := br_$(shell uname -m)                           # library name
-LIBS      := $(strip -l$(LIB))
+LIB       := $(strip $(LIB))
+LIBFILE   := ${BRLIBDIR}/lib$(strip ${LIB}).a
+LIBS      := $(addprefix -l,$(strip $(LIB)))
 
 DEP_FN    := $(SRC_FN)
 DEP       := $(addprefix $(DEPDIR)/,$(DEP_FN:.c=.d))
@@ -102,7 +104,7 @@ endif
 # if no version, use last commit and date.
 # else, if last commit != last tag commit, add commit and date to version number
 ifeq ($(VERSION),)
-  VERSION := $(build)-$(COMMIT)-$(DATE)
+  VERSION := $(build)-git.$(COMMIT)-$(DATE)
 else ifneq ($(COMMIT), $(TAG_COMMIT))
   VERSION := $(VERSION)-next-$(build)-$(COMMIT)-$(DATE)
 endif
@@ -124,7 +126,7 @@ else # ifeq ($(build),dev)
         #        fen.c
         #CPPFLAGS  += -DDEBUG_FEN                           # FEN decoding
         #        hash / TT
-        #CPPFLAGS  += -DZOBRIST_VERIFY                      # double chk zobrist
+        CPPFLAGS  += -DZOBRIST_VERIFY                       # double chk zobrist
         #CPPFLAGS  += -DPERFT_MOVE_HISTORY                  # perft, keep prev moves
         #        attack.c
         #CPPFLAGS  += -DDEBUG_ATTACK_ATTACKERS              # sq_attackers
@@ -135,7 +137,6 @@ else # ifeq ($(build),dev)
         #        old unused flags
         #CPPFLAGS  += -DDEBUG_POS                           # position.c
         #CPPFLAGS  += -DDEBUG_MOVE                          # move generation
-        #CPPFLAGS  += -DDEBUG_EVAL                          # eval functions
 endif
 
 # remove extraneous spaces (due to spaces before comments)
@@ -158,22 +159,22 @@ ifeq ($(build),release)
         #CFLAGS    += -g
         #CFLAGS    += -ginline-points                   # inlined funcs debug info
         LDFLAGS   += -flto
+else ifeq ($(build),perf)
+        CFLAGS    += -O3
+        CFLAGS    += -ggdb0                            # symbols (gdb, perf, etc.)
+        CFLAGS    += -ginline-points                   # inlined funcs debug info
+        CFLAGS    += -funroll-loops
 else ifeq ($(build),dev)
-        CFLAGS    += -Og
-        CFLAGS    += -g                                # symbols (gdb, perf, etc.)
+        CFLAGS    += -O1
+        CFLAGS    += -ggdb                             # symbols (gdb, perf, etc.)
         CFLAGS    += -ginline-points                   # inlined funcs debug info
         #CFLAGS += -pg                                 # gprof
         # Next one may be useful for valgrind (when invalid instructions)
         #CFLAGS += -mno-tbm
-else ifeq ($(build),perf)
-        CFLAGS    += -O3
-        CFLAGS    += -g                                # symbols (gdb, perf, etc.)
-        CFLAGS    += -ginline-points                   # inlined funcs debug info
-        CFLAGS    += -funroll-loops
 else ifeq ($(build),debug)
-        CFLAGS    += -Og
-        CFLAGS    += -g                                # symbols (gdb, perf, etc.)
-        CFLAGS    += -ginline-points                   # inlined funcs debug info
+        CFLAGS    += -O0                               # -Og hides some variables
+        CFLAGS    += -ggdb3                            # symbols (including macro)
+        #CFLAGS    += -ginline-points                   # inlined funcs debug info
         # for gprof
         #CFLAGS += -pg
         # Next one may be useful for valgrind (when invalid instructions)
@@ -228,16 +229,16 @@ else
 all: libs testing $(TARGET)
 
 release:
-	$(MAKE) BUILD=release clean all
+	$(MAKE) build=release clean all
 
 dev:
-	$(MAKE) BUILD=dev clean all
+	$(MAKE) build=dev clean all
 
 perf:
-	$(MAKE) BUILD=perf clean all
+	$(MAKE) build=perf clean all
 
 debug:
-	$(MAKE) BUILD=debug clean all
+	$(MAKE) build=debug clean all
 
 compile: brlib objs
 
@@ -345,6 +346,7 @@ brlib:
 	$(info calling with build=$(build))
 	$(MAKE) -e -C $(BRLIB) lib-static
 unexport build
+
 ##################################### brchess binaries
 .PHONY: targets cleanbin cleanbindir
 
@@ -356,9 +358,9 @@ cleanbin:
 cleanbindir:
 	$(call rmdir,$(BINDIR),binaries)
 
-$(TARGET): libs $(OBJ) | $(BINDIR)
+$(TARGET): $(LIBFILE) $(OBJ) | $(BINDIR) libs
 	@echo linking $@.
-	$(CC) $(LDFLAGS) $(OBJ) $(LIBS) -o $@
+	$(CC) $(ALL_LDFLAGS) $(OBJ) -o $@
 
 ##################################### pre-processed (.i) and assembler (.s) output
 .PHONY: cleanasmcpp
@@ -415,12 +417,13 @@ TEST          += movedo-test perft-test tt-test
 
 PIECE_OBJS    := piece.o
 FEN_OBJS      := $(PIECE_OBJS) fen.o position.o bitboard.o board.o \
-	hq.o attack.o hash.o init.o misc.o alloc.o move.o eval-defs.o
+	hq.o attack.o hash.o init.o util.o alloc.o move.o \
+	eval.o eval-defs.o eval-simple.o hist.o
 BB_OBJS       := $(FEN_OBJS)
 MOVEGEN_OBJS  := $(BB_OBJS) move-gen.o
 ATTACK_OBJS   := $(MOVEGEN_OBJS)
 MOVEDO_OBJS   := $(ATTACK_OBJS) move-do.o
-PERFT_OBJS    := $(MOVEDO_OBJS) search.o
+PERFT_OBJS    := $(MOVEDO_OBJS) perft.o
 TT_OBJS       := $(MOVEDO_OBJS)
 
 TEST          := $(addprefix $(BINDIR)/,$(TEST))
@@ -490,6 +493,7 @@ wtf:
 	@#echo LIBSRC=$(LIBSRC)
 
 zob:
+	echo $(LIBFILE)
 	@#$(CC) $(LDFLAGS) $(CPPFLAGS) $(CFLAGS) $< $(LIBS) src/util.c -o util
 
 ##################################### End of multi-targets

src/bitboard.h

@@ -182,19 +182,6 @@ static __always_inline bitboard_t bb_file(int file)
 }
 */
 
-/**
- * bb_first_bb() - return bitboard of first square of a bitboard.
- * @bb: bitboard
- *
- * bb must be non-zero.
- *
- * @return: bitboard of first square (lsb) of @bb.
- */
-static __always_inline square_t bb_first_bb(bitboard_t bb)
-{
-    return bb & -bb;
-}
-
 /**
  * bb_next() - clear and return next (lsb) square of a bitboard.
  * @bb: &bitboard
@@ -205,7 +192,7 @@ static __always_inline square_t bb_first_bb(bitboard_t bb)
  */
 static __always_inline square_t bb_next(bitboard_t *bb)
 {
-    square_t sq = ctz64(*bb);
+    square_t sq = lsb64(*bb);
     *bb &= *bb - 1;
     return sq;
 }

src/brchess.c

@@ -13,9 +13,6 @@
 
 
 #include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <ctype.h>
 #include <unistd.h>
 
 #include <brlib.h>

src/chessdefs.h

@@ -16,9 +16,10 @@
 
 #include <brlib.h>                                /* brlib types */
 
-#define ONE                1ul
 #define U64(const_u64)     const_u64##UL
-#define BIT(i)             ( (u64) (ONE << (i)) )
+#define BIT(i)             ( U64(1) << (i) )
+#define BIT_NONE           ( U64(0) )
+#define BIT_ALL            ( ~BIT_NONE )
 
 #define BOARDSIZE          (8*8)
 #define GAMESIZE           1024                   /* max game size (512 moves) */
@@ -50,7 +51,7 @@
 
 /* castle_t bits structure
  */
-typedef enum {
+enum {
     CASTLE_NONE = 0,
     CASTLE_WK   = (1 << 0),                       /* 0001 */
     CASTLE_WQ   = (1 << 1),                       /* 0010 */
@@ -64,7 +65,9 @@ typedef enum {
     CASTLE_K  = (1 << 0),                         /* generic K/Q, bits 0 and 1 */
     CASTLE_Q  = (1 << 1),
     CASTLE_KQ = (CASTLE_K |CASTLE_Q),
-} castle_rights_t;
+};
+
+typedef u8 castle_rights_t;
 
 /* determine is oo or ooo is possible with castle flags f and color c
  */
@@ -142,42 +145,6 @@ typedef u8 dir_t;
 #define sq_upwest(up)     ((up) - 1)
 #define sq_upeast(up)     ((up) + 1)
 
-#include <time.h>
-
-typedef struct mclock {
-    clockid_t clocktype;
-    ulong elapsed_l;
-    double elapsed_f;
-    struct timespec start;
-} mclock_t;
-
-#define CLOCK_WALL    CLOCK_REALTIME
-#define CLOCK_SYSTEM  CLOCK_MONOTONIC_RAW
-#define CLOCK_PROCESS CLOCK_PROCESS_CPUTIME_ID
-#define CLOCK_THREAD  CLOCK_THREAD_CPUTIME_ID
-
-/**
- * CLOCK_DEFINE - define a clock type.
- * @name: clock name
- * @type: clock type
- *
- * This macro is equivalent to:
- *   mclock_t name;
- *   clock_init(&name, type);
- */
-#define CLOCK_DEFINE(name, type) struct mclock name = { .clocktype = type }
-
-void clock_init(mclock_t *clock, clockid_t type);
-void clock_start(mclock_t *clock);
-s64 clock_elapsed_μs(mclock_t *clock);
-s64 clock_elapsed_ms(mclock_t *clock);
-double clock_elapsed_sec(mclock_t *clock);
-
-#define RAND_SEED_DEFAULT U64(0xb0d1ccea)
-
-void rand_init(u64 seed);
-u64 rand64(void);
-
 void init_all(void);
 
 #endif  /* _CHESSDEFS_H */

src/eval-defs.c

@@ -1,4 +1,4 @@
-/* eval-values.c - eval static definitions.
+/* eval-values.c - eval parameters
  *
  * Copyright (C) 2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -18,9 +18,70 @@
 #include "position.h"
 #include "piece.h"
 #include "eval-defs.h"
+#include "util.h"
 //#include "eval-simple.h"
 //#include "eval.h"
 
+/* eval parameters definition. */
+static const struct ev_params ev_param_def [EV_PARAMS_NB] = {
+    /*                type      setable def   min    max  name */
+    [WT_MAT]  =     { PAR_SPN,  true,   100,    0,   400, "material weight" },
+    [WT_PST]  =     { PAR_SPN,  true,   100,    0,   400, "pst weight" },
+    [TST_CHK] =     { PAR_CHK,  true,     1,    0,     0, "test check" },
+    [TST_SPN] =     { PAR_BTN,  true,     0,    0,     0, "test button" },
+
+};
+
+void param_init()
+{
+    for (int i = 0; i < EV_PARAMS_NB; ++i)
+        parameters[i] = ev_param_def[i].init;
+}
+
+int param_find_name(char *name)
+{
+    for (int i = 0; i < EV_PARAMS_NB; ++i)
+        if (str_eq_case(ev_param_def[i].name, name))
+            return i;
+    return -1;
+}
+char *param_name(const int num)
+{
+    return ev_param_def[num].name;
+}
+
+eval_t param_default(const int num)
+{
+    return ev_param_def[num].init;
+}
+eval_t param_min(const int num)
+{
+    return ev_param_def[num].min;
+}
+eval_t param_max(const int num)
+{
+    return ev_param_def[num].max;
+}
+bool param_setable(const int num)
+{
+    return ev_param_def[num].setable;
+}
+int param_type(const int num)
+{
+    return ev_param_def[num].type;
+}
+
+/* parameters in use */
+eval_t parameters[EV_PARAMS_NB];
+void param_set(int num, eval_t val)
+{
+    if (num >= 0 && num < EV_PARAMS_NB &&
+        val >= param_min(num) && val <= param_max(num)) {
+        parameters[num] = val;
+    }
+}
+
+
 /*
  * Piece-square tables. For easier reading, they are defined for black side:
  *
@@ -31,38 +92,46 @@
  *        A1 .... H1
  *      }
  */
-const struct pst pst_defs[] = {
-    {
+static const struct pst {
+    char *name;                                   /* one word only, no spaces */
+    int val[PIECE_TYPE_NB][PHASE_NB][SQUARE_NB];  /* MG then EG */
+} pst_defs[PST_NB] = {
+    [PST_ROFCHADE] = {
         /*
          * rofchade:
          * https://www.talkchess.com/forum3/viewtopic.php?f=2&t=68311&start=19
          */
-        "rofchade",
+        "Rofchade",
         {
+            /* A8 ..... H8
+             * ...........
+             * A1 ..... H1
+             */
             [PAWN] = {
                 {                                 /* midgame */
-                    0,   0,   0,   0,   0,   0,  0,   0,
-                    98, 134,  61,  95,  68, 126, 34, -11,
-                    -6,   7,  26,  31,  65,  56, 25, -20,
+                    + 0,   0,   0,   0,   0,   0,  0,   0,
+                    +98, 134,  61,  95,  68, 126, 34, -11,
+                    - 6,   7,  26,  31,  65,  56, 25, -20,
                     -14,  13,   6,  21,  23,  12, 17, -23,
                     -27,  -2,  -5,  12,  17,   6, 10, -25,
                     -26,  -4,  -4, -10,   3,   3, 33, -12,
                     -35,  -1, -20, -23, -15,  24, 38, -22,
-                    0,   0,   0,   0,   0,   0,  0,   0,
+                    + 0,   0,   0,   0,   0,   0,  0,   0,
                 },
                 {                                 /* endgame */
-                    0,   0,   0,   0,   0,   0,   0,   0,
+                    + 0,   0,   0,   0,   0,   0,   0,   0,
                     178, 173, 158, 134, 147, 132, 165, 187,
-                    94, 100,  85,  67,  56,  53,  82,  84,
-                    32,  24,  13,   5,  -2,   4,  17,  17,
-                    13,   9,  -3,  -7,  -7,  -8,   3,  -1,
-                    4,   7,  -6,   1,   0,  -5,  -1,  -8,
-                    13,   8,   8,  10,  13,   0,   2,  -7,
-                    0,   0,   0,   0,   0,   0,   0,   0,
+                    +94, 100,  85,  67,  56,  53,  82,  84,
+                    +32,  24,  13,   5,  -2,   4,  17,  17,
+                    +13,   9,  -3,  -7,  -7,  -8,   3,  -1,
+                    + 4,   7,  -6,   1,   0,  -5,  -1,  -8,
+                    +13,   8,   8,  10,  13,   0,   2,  -7,
+                    + 0,   0,   0,   0,   0,   0,   0,   0,
                 }
             },
             [KNIGHT] = {
-                {                                 /* midgame */
+                {
+                    /* midgame */
                     -167, -89, -34, -49,  61, -97, -15, -107,
                     -73, -41,  72,  36,  23,  62,   7,  -17,
                     -47,  60,  37,  65,  84, 129,  73,   44,
@@ -88,18 +157,18 @@ const struct pst pst_defs[] = {
                     -29,  4, -82, -37, -25, -42,   7,  -8,
                     -26, 16, -18, -13,  30,  59,  18, -47,
                     -16, 37,  43,  40,  35,  50,  37,  -2,
-                     -4,  5,  19,  50,  37,  37,   7,  -2,
-                     -6, 13,  13,  26,  34,  12,  10,   4,
-                      0, 15,  15,  15,  14,  27,  18,  10,
-                      4, 15,  16,   0,   7,  21,  33,   1,
+                    - 4,  5,  19,  50,  37,  37,   7,  -2,
+                    - 6, 13,  13,  26,  34,  12,  10,   4,
+                    + 0, 15,  15,  15,  14,  27,  18,  10,
+                    + 4, 15,  16,   0,   7,  21,  33,   1,
                     -33, -3, -14, -21, -13, -12, -39, -21,
                 },
                 {                                 /* endgame */
                     -14, -21, -11,  -8, -7,  -9, -17, -24,
-                     -8,  -4,   7, -12, -3, -13,  -4, -14,
-                      2,  -8,   0,  -1, -2,   6,   0,   4,
-                     -3,   9,  12,   9, 14,  10,   3,   2,
-                     -6,   3,  13,  19,  7,  10,  -3,  -9,
+                    - 8,  -4,   7, -12, -3, -13,  -4, -14,
+                    + 2,  -8,   0,  -1, -2,   6,   0,   4,
+                    - 3,   9,  12,   9, 14,  10,   3,   2,
+                    - 6,   3,  13,  19,  7,  10,  -3,  -9,
                     -12,  -3,   8,  10, 13,   3,  -7, -15,
                     -14, -18,  -7,  -1,  4,  -9, -15, -27,
                     -23,  -9, -23,  -5, -9, -16,  -5, -17,
@@ -107,9 +176,9 @@ const struct pst pst_defs[] = {
             },
             [ROOK] = {
                 {                                 /* midgame */
-                    32,  42,  32,  51, 63,  9,  31,  43,
-                    27,  32,  58,  62, 80, 67,  26,  44,
-                    -5,  19,  26,  36, 17, 45,  61,  16,
+                    +32,  42,  32,  51, 63,  9,  31,  43,
+                    +27,  32,  58,  62, 80, 67,  26,  44,
+                    - 5,  19,  26,  36, 17, 45,  61,  16,
                     -24, -11,   7,  26, 24, 35,  -8, -20,
                     -36, -26, -12,  -1,  9, -7,   6, -23,
                     -45, -25, -16, -17,  3,  0,  -5, -33,
@@ -119,9 +188,9 @@ const struct pst pst_defs[] = {
                 {                                 /* endgame */
                     13, 10, 18, 15, 12,  12,   8,   5,
                     11, 13, 13, 11, -3,   3,   8,   3,
-                    7,  7,  7,  5,  4,  -3,  -5,  -3,
-                    4,  3, 13,  1,  2,   1,  -1,   2,
-                    3,  5,  8,  4, -5,  -6,  -8, -11,
+                    +7,  7,  7,  5,  4,  -3,  -5,  -3,
+                    +4,  3, 13,  1,  2,   1,  -1,   2,
+                    +3,  5,  8,  4, -5,  -6,  -8, -11,
                     -4,  0, -5, -1, -7, -12,  -8, -16,
                     -6, -6,  0,  2, -9,  -9, -11,  -3,
                     -9,  2,  3, -1, -5, -13,   4, -20,
@@ -133,16 +202,16 @@ const struct pst pst_defs[] = {
                     -24, -39,  -5,   1, -16,  57,  28,  54,
                     -13, -17,   7,   8,  29,  56,  47,  57,
                     -27, -27, -16, -16,  -1,  17,  -2,   1,
-                    -9, -26,  -9, -10,  -2,  -4,   3,  -3,
+                    - 9, -26,  -9, -10,  -2,  -4,   3,  -3,
                     -14,   2, -11,  -2,  -5,   2,  14,   5,
                     -35,  -8,  11,   2,   8,  15,  -3,   1,
-                    -1, -18,  -9,  10, -15, -25, -31, -50,
+                    - 1, -18,  -9,  10, -15, -25, -31, -50,
                 },
                 {                                 /* endgame */
-                    -9,  22,  22,  27,  27,  19,  10,  20,
+                    - 9,  22,  22,  27,  27,  19,  10,  20,
                     -17,  20,  32,  41,  58,  25,  30,   0,
                     -20,   6,   9,  49,  47,  35,  19,   9,
-                    3,  22,  24,  45,  57,  40,  57,  36,
+                    + 3,  22,  24,  45,  57,  40,  57,  36,
                     -18,  28,  19,  47,  31,  34,  39,  23,
                     -16, -27,  15,   6,   9,  17,  10,   5,
                     -22, -23, -30, -16, -16, -23, -36, -32,
@@ -152,19 +221,19 @@ const struct pst pst_defs[] = {
             [KING] = {                            /* midgame */
                 {
                     -65,  23,  16, -15, -56, -34,   2,  13,
-                    29,  -1, -20,  -7,  -8,  -4, -38, -29,
-                    -9,  24,   2, -16, -20,   6,  22, -22,
+                    +29,  -1, -20,  -7,  -8,  -4, -38, -29,
+                    - 9,  24,   2, -16, -20,   6,  22, -22,
                     -17, -20, -12, -27, -30, -25, -14, -36,
                     -49,  -1, -27, -39, -46, -44, -33, -51,
                     -14, -14, -22, -46, -44, -30, -15, -27,
-                    1,   7,  -8, -64, -43, -16,   9,   8,
+                    + 1,   7,  -8, -64, -43, -16,   9,   8,
                     -15,  36,  12, -54,   8, -28,  24,  14,
                 },
                 {                                 /* endgame */
                     -74, -35, -18, -18, -11,  15,   4, -17,
                     -12,  17,  14,  17,  17,  38,  23,  11,
-                    10,  17,  23,  15,  20,  45,  44,  13,
-                    -8,  22,  24,  27,  26,  33,  26,   3,
+                    +10,  17,  23,  15,  20,  45,  44,  13,
+                    - 8,  22,  24,  27,  26,  33,  26,   3,
                     -18,  -4,  21,  24,  27,  23,   9, -11,
                     -19,  -3,  11,  21,  23,  16,   7,  -9,
                     -27, -11,   4,  13,  14,   4,  -5, -17,
@@ -172,35 +241,40 @@ const struct pst pst_defs[] = {
                 }
             }
         }
-    },                                            /* CPW */
-    {
+    },                                            /* rofchade end */
+
+    [PST_CPW] = {
         /*
          * CPW:
          * https://www.chessprogramming.org/Simplified_Evaluation_Function
          * Note: ≠ https://github.com/nescitus/cpw-engine
          */
-        "cpw",
+        "CPW",
         {
+            /* A8 ..... H8
+             * ...........
+             * A1 ..... H1
+             */
             [PAWN] = {
                 {                                 /* midgame */
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                     50, 50,  50,  50,  50,  50, 50, 50,
                     10, 10,  20,  30,  30,  20, 10, 10,
-                    5,  5,  10,  25,  25,  10,  5,  5,
-                    0,  0,   0,  20,  20,   0,  0,  0,
-                    5, -5, -10,   0,   0, -10, -5,  5,
-                    5, 10,  10, -20, -20,  10, 10,  5,
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +5,  5,  10,  25,  25,  10,  5,  5,
+                    +0,  0,   0,  20,  20,   0,  0,  0,
+                    +5, -5, -10,   0,   0, -10, -5,  5,
+                    +5, 10,  10, -20, -20,  10, 10,  5,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                 },
                 {                                 /* endgame */
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                     50, 50,  50,  50,  50,  50, 50, 50,
                     10, 10,  20,  30,  30,  20, 10, 10,
-                    5,  5,  10,  25,  25,  10,  5,  5,
-                    0,  0,   0,  20,  20,   0,  0,  0,
-                    5, -5, -10,   0,   0, -10, -5,  5,
-                    5, 10,  10, -20, -20,  10, 10,  5,
-                    0,  0,   0,   0,   0,   0,  0,  0,
+                    +5,  5,  10,  25,  25,  10,  5,  5,
+                    +0,  0,   0,  20,  20,   0,  0,  0,
+                    +5, -5, -10,   0,   0, -10, -5,  5,
+                    +5, 10,  10, -20, -20,  10, 10,  5,
+                    +0,  0,   0,   0,   0,   0,  0,  0,
                 },
             },
             [KNIGHT] = {
@@ -249,24 +323,24 @@ const struct pst pst_defs[] = {
             },
             [ROOK] = {
                 {                                 /* midgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
                 {                                 /* endgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
             },
             [QUEEN] = {
@@ -274,8 +348,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -10,   0,   5,  5,  5,   5,   0, -10,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
+                    - 5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   5,   5,  5,  5,   5,   0, -10,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -284,8 +358,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -10,   0,   5,  5,  5,   5,   0, -10,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
+                    - 5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   5,   5,  5,  5,   5,   0, -10,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -299,8 +373,8 @@ const struct pst pst_defs[] = {
                     -30, -40, -40, -50, -50, -40, -40, -30,
                     -20, -30, -30, -40, -40, -30, -30, -20,
                     -10, -20, -20, -20, -20, -20, -20, -10,
-                    20,  20,   0,   0,   0,   0,  20,  20,
-                    20,  30,  10,   0,   0,  10,  30,  20,
+                    +20,  20,   0,   0,   0,   0,  20,  20,
+                    +20,  30,  10,   0,   0,  10,  30,  20,
                 },
                 {                                 /* endgame */
                     -50, -40, -30, -20, -20, -30, -40, -50,
@@ -314,14 +388,19 @@ const struct pst pst_defs[] = {
                 }
             }
         }
-    },                                            /* CPW */
-    {
+    },                                            /* CPW end */
+
+    [PST_SJENG] = {
         /*
          * sjeng: https://github.com/gcp/sjeng
          * Rook and Queen from CPW.
          */
-        "sjeng",
+        "Sjeng",
         {
+            /* A8 ..... H8
+             * ...........
+             * A1 ..... H1
+             */
             [PAWN] = {
                 {                                 /* midgame */
                     0,  0,  0,  0,  0,  0,  0, 0,
@@ -390,24 +469,24 @@ const struct pst pst_defs[] = {
             },
             [ROOK] = {
                 {                                 /* midgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
                 {                                 /* endgame */
-                    0,  0,  0,  0,  0,  0,  0,  0,
-                    5, 10, 10, 10, 10, 10, 10,  5,
+                    +0,  0,  0,  0,  0,  0,  0,  0,
+                    +5, 10, 10, 10, 10, 10, 10,  5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
                     -5,  0,  0,  0,  0,  0,  0, -5,
-                    0,  0,  0,  5,  5,  0,  0,  0,
+                    +0,  0,  0,  5,  5,  0,  0,  0,
                 },
             },
             [QUEEN] = {
@@ -415,8 +494,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -10,   5,   5,  5,  5,   5,   0, -10,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
+                    -05,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   0,   5,  5,  5,   5,   0, -10,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -425,8 +504,8 @@ const struct pst pst_defs[] = {
                     -20, -10, -10, -5, -5, -10, -10, -20,
                     -10,   0,   5,  0,  0,   0,   0, -10,
                     -10,   5,   5,  5,  5,   5,   0, -10,
-                    0,   0,   5,  5,  5,   5,   0,  -5,
-                    -5,   0,   5,  5,  5,   5,   0,  -5,
+                    + 0,   0,   5,  5,  5,   5,   0,  -5,
+                    - 5,   0,   5,  5,  5,   5,   0,  -5,
                     -10,   0,   5,  5,  5,   5,   0, -10,
                     -10,   0,   0,  0,  0,   0,   0, -10,
                     -20, -10, -10, -5, -5, -10, -10, -20,
@@ -438,88 +517,78 @@ const struct pst pst_defs[] = {
                     -34, -34, -55, -55, -55, -55, -34, -34,
                     -21, -21, -34, -34, -34, -34, -21, -21,
                     -13, -13, -21, -21, -21, -21, -13, -13,
-                    -8,  -8, -13, -13, -13, -13,  -8,  -8,
-                    -5,  -5,  -8,  -8,  -8,  -8,  -5,  -5,
-                    -3,  -5,  -6,  -6,  -6,  -6,  -5,  -3,
-                    2,  14,   0,   0,   0,   9,  14,   2,
+                    - 8,  -8, -13, -13, -13, -13,  -8,  -8,
+                    - 5,  -5,  -8,  -8,  -8,  -8,  -5,  -5,
+                    - 3,  -5,  -6,  -6,  -6,  -6,  -5,  -3,
+                    + 2,  14,   0,   0,   0,   9,  14,   2,
                 },
                 {                                 /* endgame */
                     -5, -3, -1,  0,  0, -1, -3, -5,
                     -3, 10, 10, 10, 10, 10, 10, -3,
                     -1, 10, 25, 25, 25, 25, 10, -1,
-                    0, 10, 25, 30, 30, 25, 10,  0,
-                    0, 10, 25, 30, 30, 25, 10,  0,
+                    +0, 10, 25, 30, 30, 25, 10,  0,
+                    +0, 10, 25, 30, 30, 25, 10,  0,
                     -1, 10, 25, 25, 25, 25, 10, -1,
                     -3, 10, 10, 10, 10, 10, 10, -3,
                     -5, -3, -1,  0,  0, -1, -3, -5,
                 }
             }
         },
-    },                                            /* sjeng */
+    },                                            /* sjeng end */
 };
 
-const int nb_pc_sq = ARRAY_SIZE(pst_defs);        /* # of predefined pc_sq tables */
-int pst_current = 0;
-int pst_mg[COLOR_NB][PT_NB][SQUARE_NB];
-int pst_eg[COLOR_NB][PT_NB][SQUARE_NB];
+int pst_current = PST_DEFAULT;
+eval_t pst_mg[COLOR_NB][PT_NB][SQUARE_NB];
+eval_t pst_eg[COLOR_NB][PT_NB][SQUARE_NB];
 
-/* phase calculation from Fruit:
- * https://github.com/Warpten/Fruit-2.1
-*/
-
-/**
- * calc_phase - calculate position phase
- * @pos: &position
- *
- * This function should be calculated when a new position is setup, or as
- * a verification of an incremental one.
- * phase is clamped between 0 (opening) and 24 (ending).
- *
- * @return:
- */
-s16 calc_phase(pos_t *pos)
+void pst_set(char *str)
 {
-    int phase = ALL_PHASE;
-    phase -= P_PHASE * popcount64(pos->bb[WHITE][PAWN] | pos->bb[BLACK][PAWN]);
-    phase -= N_PHASE * popcount64(pos->bb[WHITE][KNIGHT] | pos->bb[BLACK][KNIGHT]);
-    phase -= B_PHASE * popcount64(pos->bb[WHITE][BISHOP] | pos->bb[BLACK][BISHOP]);
-    phase -= R_PHASE * popcount64(pos->bb[WHITE][ROOK] | pos->bb[BLACK][ROOK]);
-    phase -= Q_PHASE * popcount64(pos->bb[WHITE][QUEEN] | pos->bb[BLACK][QUEEN]);
-
-    phase = clamp(phase, 0, ALL_PHASE);
-#   ifdef DEBUG_EVAL
-    printf("calc phase:%d\n", phase);
-#   endif
-    return phase;
+    pst_init(pst_find(str));
 }
 
-static int pst_find(char *str)
+int pst_find(char *str)
 {
-    for (int i = 0; i < nb_pc_sq; ++i)
-        if (!strcmp(pst_defs[i].name, str))
+    for (int i = 0; i < PST_NB; ++i) {
+        if (str_eq_case(pst_defs[i].name, str))
             return i;
+    }
     return -1;
 }
 
-void pst_init(char *name)
+void pst_init(int set)
 {
-    const struct pst *cur;
-    int set = pst_find(name);
-#   ifdef DEBUG_EVAL
-    printf("initializing piece-square tables `%s`(%d)\n", name, set);
-#   endif
-    if (set < 0)
+    const struct pst *pst;
+
+    if (warn(set < 0 || set >= PST_NB, "wrong PST, defaulting to zero."))
         set = 0;
 
-    cur = pst_defs + set;
-    pst_current = set;
-    for (piece_type_t pt = PAWN; pt < PT_NB; ++pt) {
-        for (square_t sq = 0; sq < SQUARE_NB; ++sq) {
-            pst_mg[BLACK][pt][sq] = cur->val[MIDGAME][pt][sq];
-            pst_mg[WHITE][pt][sq] = cur->val[MIDGAME][pt][FLIP_V(sq)];
+#   ifdef DEBUG_EVAL2
+    printf("initializing piece-square tables %d ('%s')\n", set, pst_defs[set].name);
+#   endif
 
-            pst_eg[BLACK][pt][sq] = cur->val[ENDGAME][pt][sq];
-            pst_eg[WHITE][pt][sq] = cur->val[ENDGAME][pt][FLIP_V(sq)];
+    pst = pst_defs + set;
+    pst_current = set;
+    int wmat = param(WT_MAT);
+    int wpst = param(WT_PST);
+    for (piece_type_t pt = PAWN; pt < PT_NB; ++pt) {
+        eval_t mid_pc = piece_midval(pt);
+        eval_t end_pc = piece_endval(pt);
+        for (square_t sq = 0; sq < SQUARE_NB; ++sq) {
+            eval_t mid_pst = pst->val[pt][MIDGAME][sq];
+            eval_t end_pst = pst->val[pt][ENDGAME][sq];
+
+            pst_mg[BLACK][pt][sq] = (mid_pc * wmat + mid_pst * wpst) / 100;
+            pst_eg[BLACK][pt][sq] = (end_pc * wmat + end_pst * wpst) / 100;
+
+            pst_mg[WHITE][pt][FLIP_V(sq)] =  pst_mg[BLACK][pt][sq];
+            pst_eg[WHITE][pt][FLIP_V(sq)] =  pst_eg[BLACK][pt][sq];
         }
     }
 }
+
+char *pst_name(int i)
+{
+    if (i >= 0 && i < PST_NB)
+        return pst_defs[i].name;
+    return "undef";
+}

src/eval-defs.h

@@ -0,0 +1,121 @@
+/* eval-defs.h - eval parameters
+ *
+ * Copyright (C) 2024 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef EVAL_DEFS_H
+#define EVAL_DEFS_H
+
+
+#include "chessdefs.h"
+#include "piece.h"
+#include "eval.h"
+
+/* game phases
+ */
+enum {
+    MIDGAME,
+    ENDGAME,
+    PHASE_NB
+};
+typedef s16 phase_t;
+
+/* pieces weight in phase calculation.
+ */
+enum {
+    P_PHASE = 0,
+    N_PHASE = 1,
+    B_PHASE = 1,
+    R_PHASE = 2,
+    Q_PHASE = 4,
+    ALL_PHASE = P_PHASE*16 + N_PHASE*4 + B_PHASE*4 + R_PHASE*4 + Q_PHASE*2
+};
+
+/* max pieces eval is 9*QUEEN_VALUE + 2*ROOK_VALUE + 2*BISHOP_VALUE
+ * + 2*KNIGHT_VALUE which is (for a pawn valued at 100) well less than 15,000.
+ */
+#define EVAL_MAX     (SHRT_MAX)                   /* 32767 */
+#define EVAL_MIN     (-EVAL_MAX)
+
+#define EVAL_INV     EVAL_MIN
+
+#define EVAL_MATE    30000
+
+/* eval parameters */
+enum {
+    WT_MAT,
+    WT_PST,
+
+    TST_SPN,
+    TST_CHK,
+
+    EV_PARAMS_NB
+};
+
+enum {
+    PAR_CHK,
+    PAR_SPN,
+    PAR_BTN,
+    PAR_STR,
+};
+
+/**
+ * ev_params - parameters definition
+ * @init: eval_t default value
+ * @min, @max: eval_t min and max values
+ * @type: variable type (PARAM_CHECK, etc...)
+ * @setable: bool setable (proposed in UCI options)
+ * @name: char * human readable name
+ */
+struct ev_params {
+    int type;
+    bool setable;                                 /* true: proposed in UCI options */
+    eval_t init, min, max;
+    char *name;
+};
+void param_init(void);
+int param_find_name(char *name);                  /* find parameter number by name */
+char *param_name(const int num);
+
+eval_t param_default(const int num);              /* get default param value */
+eval_t param_min(const int num);
+eval_t param_max(const int num);
+bool param_setable(const int num);
+int param_type(const int num);
+
+/* parameters in use */
+extern eval_t parameters[EV_PARAMS_NB];
+#define param(n) parameters[n]
+void param_set (int num, eval_t val);
+
+/* PST data */
+/**
+ * pst_defs - pre-defined piece-square tables.
+ */
+enum {
+    PST_ROFCHADE,
+    PST_CPW,
+    PST_SJENG,
+    PST_NB
+};
+
+#define PST_DEFAULT PST_CPW
+extern int pst_current;
+extern eval_t pst_mg[COLOR_NB][PT_NB][SQUARE_NB];
+extern eval_t pst_eg[COLOR_NB][PT_NB][SQUARE_NB];
+
+void pst_set(char *str);
+int pst_find(char *str);
+void pst_init(int pst);
+
+char *pst_name(int i);
+
+#endif  /* EVAL_DEFS_H */

src/eval-simple.c

@@ -70,7 +70,7 @@ eval_t eval_simple(pos_t *pos)
             while (bb) {
                 square_t sq = bb_next(&bb);
                 mg_eval[color] += pst_mg[color][pt][sq];
-                eg_eval[color] += pst_mg[color][pt][sq];
+                eg_eval[color] += pst_eg[color][pt][sq];
             }
 
 #           ifdef DEBUG_EVAL

src/eval.c

@@ -20,6 +20,47 @@
 #include "eval.h"
 #include "eval-simple.h"
 
+/**
+ * calc_phase - calculate position phase
+ * @pos: &position
+ *
+ * This function should be calculated when a new position is setup, or as
+ * a verification of an incremental one.
+ * phase is clamped between 0 (opening) and 24 (ending).
+ *
+ * @return:
+ */
+s16 calc_phase(pos_t *pos)
+{
+    int phase = ALL_PHASE;
+    phase -= P_PHASE * popcount64(pos->bb[WHITE][PAWN]   | pos->bb[BLACK][PAWN]);
+    phase -= N_PHASE * popcount64(pos->bb[WHITE][KNIGHT] | pos->bb[BLACK][KNIGHT]);
+    phase -= B_PHASE * popcount64(pos->bb[WHITE][BISHOP] | pos->bb[BLACK][BISHOP]);
+    phase -= R_PHASE * popcount64(pos->bb[WHITE][ROOK]   | pos->bb[BLACK][ROOK]);
+    phase -= Q_PHASE * popcount64(pos->bb[WHITE][QUEEN]  | pos->bb[BLACK][QUEEN]);
+
+    phase = max(phase, 0);
+#   ifdef DEBUG_EVAL
+    printf("calculated phase:%d\n", phase);
+#   endif
+    return phase;
+}
+
+
+
+/*
+ * inline eval_t eval_mobility(pos_t *pos, bool color)
+ * {
+ *     return pos->mobility[color];
+ * }
+ *
+ *
+ * inline eval_t eval_square_control(pos_t *pos, bool color)
+ * {
+ *     return popcount64(pos->controlled[color]);
+ * }
+ */
+
 /*
  * inline eval_t eval_mobility(pos_t *pos, bool color)
  * {

src/eval.h

@@ -19,6 +19,8 @@
 #include "chessdefs.h"
 #include "eval-defs.h"
 
+s16 calc_phase(pos_t *pos);
+
 eval_t eval_mobility(pos_t *pos, bool color);
 eval_t eval_square_control(pos_t *pos, bool color);
 

src/hash.c

@@ -19,6 +19,7 @@
 #include <bug.h>
 
 #include "chessdefs.h"
+#include "util.h"
 #include "alloc.h"
 #include "position.h"
 #include "piece.h"
@@ -201,7 +202,7 @@ int tt_create(s32 sizemb)
         hash_tt.bytes    = hash_tt.nbuckets * sizeof(bucket_t);
         hash_tt.mb       = hash_tt.bytes / 1024 / 1024;
 
-        hash_tt.mask     = -1ull >> (64 - nbits);
+        hash_tt.mask     = BIT_ALL >> (64 - nbits);
 
         hash_tt.keys     = safe_alloc_aligned_hugepage(hash_tt.bytes);
 
@@ -294,6 +295,7 @@ hentry_t *tt_probe_perft(const hkey_t key, const u16 depth)
     /* find key in buckets */
     for (i = 0; i < ENTRIES_PER_BUCKET; ++i) {
         entry = bucket->entry + i;
+        bug_on(entry->key && (key & hash_tt.mask) != (entry->key & hash_tt.mask));
         if (key == entry->key && HASH_PERFT_DEPTH(entry->data) == depth) {
             hash_tt.hits++;
             /*
@@ -389,7 +391,7 @@ hentry_t *tt_store_perft(const hkey_t key, const u16 depth, const u64 nodes)
 void tt_info()
 {
     if (hash_tt.keys) {
-        printf("TT: Mb:%d buckets:%'lu (bits:%u mask:%#x) entries:%'lu\n",
+        printf("TT: Mb:%d buckets:%'lu (bits:%u mask:%#lx) entries:%'lu\n",
                hash_tt.mb, hash_tt.nbuckets, hash_tt.nbits,
                hash_tt.mask, hash_tt.nkeys);
     } else {

src/hash.h

@@ -76,15 +76,15 @@ typedef struct {
 
     /* memory size in bytes/mb */
     size_t bytes;
-    u32  mb;
+    u32 mb;
 
     /* size in buckets/keys */
     size_t nbuckets;
     size_t nkeys;                                 /* nbuckets * NBUCKETS */
 
     /* internal representation */
-    u32  nbits;                                   /* #buckets in bits, power of 2 */
-    u32  mask;                                    /* nbuckets - 1, key mask */
+    u32 nbits;                                    /* #buckets in bits, power of 2 */
+    u64 mask;                                     /* nbuckets - 1, bucket mask */
 
     /* stats - unsure about usage */
     //size_t used_buckets;
@@ -106,8 +106,8 @@ typedef struct {
 
 extern hkey_t zobrist_pieces[16][64];
 extern hkey_t zobrist_castling[4 * 4 + 1];
-extern hkey_t zobrist_turn;                        /* for black, XOR each ply */
-extern hkey_t zobrist_ep[9];                       /* 0-7: ep file, 8: SQUARE_NONE */
+extern hkey_t zobrist_turn;                       /* for black, XOR each ply */
+extern hkey_t zobrist_ep[9];                      /* 0-7: ep file, 8: SQUARE_NONE */
 
 extern hasht_t hash_tt;                           /* main transposition table */
 

src/init.c

@@ -16,7 +16,7 @@
 #include <locale.h>
 
 #include "chessdefs.h"
-
+#include "util.h"
 #include "bitboard.h"
 #include "hq.h"
 #include "eval-defs.h"
@@ -27,18 +27,23 @@
 
 void init_all(void)
 {
+    printff("initiazing system: ");
     /* line-buffered stdout */
-    printff("initiazing stdout buffering... ");
+    printff("stdout buffering... ");
     setlinebuf(stdout);
 
-    /* for printf() numeric thousands separator */
     printff("locale... ");
+    /* for printf() thousands separator */
     setlocale(LC_NUMERIC, "");
+    setlocale(LC_CTYPE, "C");
 
     /* pseudo random generator seed */
     printff("random generator... ");
     rand_init(RAND_SEED_DEFAULT);
 
+    printf("done.\n");
+
+    printff("initiazing board data: ");
     /* bitboards & hq */
     printff("bitboards... ");
     bitboard_init();
@@ -46,16 +51,25 @@ void init_all(void)
     printff("hq bitboards... ");
     hq_init();
 
+    printf("done.\n");
+
+    printff("initiazing move data: ");
     /* zobrist tables & default tt hashtable */
     printff("zobrist tables... ");
     zobrist_init();
 
-    printff("hash tables... ");
+    printff("transposition tables... ");
     tt_create(HASH_SIZE_DEFAULT);
 
+    printf("done.\n");
+
+    printff("initiazing eval data: ");
+    printf("parameters... ");
+    param_init();
+
     /* eval tables */
-    printf("pst data... ");
-    pst_init("cpw");
+    printf("pst tables... ");
+    pst_init(PST_DEFAULT);
 
     printf("done.\n");
 }

src/move-do.c

@@ -25,6 +25,20 @@
 #include "move-do.h"
 #include "hash.h"
 
+/**
+ * sq_castle - castling rights per square.
+ *
+ * position castling rights mask has to be AND'ed with this array 'from' and 'to'.
+ */
+castle_rights_t sq_castle[64] = {
+    [A1] = ~CASTLE_WQ, [B1 ... D1] = CASTLE_ALL,
+    [E1] = ~CASTLE_W,  [F1 ... G1] = CASTLE_ALL,
+    [H1] = ~CASTLE_WK, [A2 ... H7] = CASTLE_ALL,
+    [A8] = ~CASTLE_BQ, [B8 ... D8] = CASTLE_ALL,
+    [E8] = ~CASTLE_B,  [F8 ... G8] = CASTLE_ALL,
+    [H8] = ~CASTLE_BK,
+};
+
 /**
  * move_do() - do move.
  * @pos:    &pos_t position
@@ -60,9 +74,8 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
 
     *state = pos->state;                          /* save irreversible changes */
 
-    /* update key: switch turn, reset castling and ep */
+    /* update key: switch turn, reset ep */
     key ^= zobrist_turn;
-    key ^= zobrist_castling[pos->castle];
     key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
 
     ++pos->clock_50;
@@ -74,80 +87,69 @@ pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
 
     bug_on(COLOR(piece) != us);
 
-    if (is_promotion(move)) {
-        bug_on(sq_rank(to) != sq_rel_rank(RANK_8, us));
-        new_piece = MAKE_PIECE(move_promoted(move), us);
-    }
-
-    if (captured != EMPTY) {
+    /* special moves: captures, pawn double push, en-passant, castling.
+     * All these moves are exclusive (so we use if ... else)
+     */
+    if (captured != EMPTY) {                      /* capture: remove piece */
         pos->clock_50 = 0;
         bug_on(pos->board[to] == EMPTY || COLOR(pos->captured) != them);
         key ^= zobrist_pieces[captured][to];
-        pos_clr_sq(pos, to);                      /* clear square */
-    } else if (is_castle(move)) {                 /* handle rook move */
-        square_t rookfrom, rookto;
-        if (to > from) {
-            rookfrom = sq_rel(H1, us);
-            rookto = sq_rel(F1, us);
-        } else {
-            rookfrom = sq_rel(A1, us);
-            rookto = sq_rel(D1, us);
-        }
-        key ^= zobrist_pieces[pos->board[rookfrom]][rookto] ^
-            zobrist_pieces[pos->board[rookfrom]][rookfrom];
-        pos_set_sq(pos, rookto, pos->board[rookfrom]);
-        pos_clr_sq(pos, rookfrom);
-        pos->castle = clr_castle(pos->castle, us);
-    } else if (ptype == PAWN) {                   /* pawn non capture or e.p. */
+        pos_clr_sq(pos, to);
+    } else if (ptype == PAWN) {
         pos->clock_50 = 0;
-        if (from + up + up == to) {               /* if pawn double push, set e.p. */
+        if (from + up + up == to) {               /* double push: set e.p. */
             square_t ep = from + up;
+            /* check that opponent can e.p. */
             if (bb_pawn_attacks[us][ep] & pos->bb[them][PAWN]) {
                 pos->en_passant = ep;
                 key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
             }
-        } else if (is_enpassant(move)) {          /* clear grabbed pawn */
+        } else if (is_enpassant(move)) {          /* e.p.: clear grabbed pawn */
             square_t grabbed = to - up;
             piece_t pc = pos->board[grabbed];
             key ^= zobrist_pieces[pc][grabbed];
             pos_clr_sq(pos, grabbed);
         }
+    } else if (is_castle(move)) {                 /* castling: handle rook move */
+        square_t rookfrom, rookto;
+        if (to > from) {                          /* o-o */
+            rookfrom = to + 1;
+            rookto = to - 1;
+        } else {                                  /* o-o-o */
+            rookfrom = to - 2;
+            rookto = to + 1;
+        }
+        key ^= zobrist_pieces[pos->board[rookfrom]][rookto] ^
+            zobrist_pieces[pos->board[rookfrom]][rookfrom];
+        pos_set_sq(pos, rookto, pos->board[rookfrom]);
+        pos_clr_sq(pos, rookfrom);
+    }
+
+    /* common part: captures and non captures
+     * We could improve slightly, as en-passant and double push will make
+     * the following tests.
+     * Improvement could be to add promotion test and king test twice above.
+     * (in capture and after ).
+     */
+    if (is_promotion(move)) {
+        bug_on(sq_rank(to) != sq_rel_rank(RANK_8, us));
+        new_piece = MAKE_PIECE(move_promoted(move), us);
     }
 
     key ^= zobrist_pieces[piece][from] ^ zobrist_pieces[new_piece][to];
-    pos_clr_sq(pos, from);                        /* clear "from" and set "to" */
+    pos_clr_sq(pos, from);
     pos_set_sq(pos, to, new_piece);
 
-    if (ptype == KING)
-        pos->king[us] = to;
-
-    /* update castling flags
-     * As we always consider flags are valid, we :
-     * - adjust our flags if relative from is "E1", "A1", H1"
-     * - adjust opp flags if relative to   if "A8", H8"
-     */
-    if (can_castle(pos->castle, us)) {            /* do we save time with this test ? */
-        square_t rel_e1 = sq_rel(E1, us);
-        square_t rel_a1 = sq_rel(A1, us);
-        square_t rel_h1 = sq_rel(H1, us);
-        if (from == rel_e1)
-            pos->castle = clr_castle(pos->castle, us);
-        else if (from == rel_a1)
-            pos->castle = clr_ooo(pos->castle, us);
-        else if (from == rel_h1)
-            pos->castle = clr_oo(pos->castle, us);
-    }
-    if (can_castle(pos->castle, them)) {
-        square_t rel_a8 = sq_rel(A8, us);
-        square_t rel_h8 = sq_rel(H8, us);
-        if (to == rel_a8)
-            pos->castle = clr_ooo(pos->castle, them);
-        else if (to == rel_h8)
-            pos->castle = clr_oo(pos->castle, them);
-    }
-
-    /* update castling rights key */
+    /* update castling flags */
     key ^= zobrist_castling[pos->castle];
+    pos->castle &= sq_castle[from] & sq_castle[to];
+    key ^= zobrist_castling[pos->castle];
+
+    //if (ptype == KING) {
+    //    pos->king[us] = to;
+    //} else
+    /* do this always, cheaper than test on K move */
+    pos->king[us] = ctz64(pos->bb[us][KING]);
 
     pos->key = key;
 
@@ -180,33 +182,43 @@ pos_t *move_undo(pos_t *pos, const move_t move, const state_t *state)
     piece_t piece = pos->board[to];
     int up = sq_up(them);
 
+    /* common part: captures and non captures
+     * We could improve slightly, as en-passant and double push will make
+     * the following tests.
+     * Improvement could be to add promotion test and king test twice above.
+     * (in capture and after ).
+     */
     if (is_promotion(move))
         piece = MAKE_PIECE(PAWN, us);
 
-    pos_clr_sq(pos, to);                          /* always clear "to" ... */
-    pos_set_sq(pos, from, piece);                 /* ... and set "from" */
+    pos_clr_sq(pos, to);
+    pos_set_sq(pos, from, piece);
 
-    if (PIECE(piece) == KING)
-        pos->king[us] = from;
-
-    if (pos->captured != EMPTY) {
-        pos_set_sq(pos, to, pos->captured);       /* restore captured piece */
-    } else if (is_castle(move)) {                 /* make reverse rook move */
+    /* special moves: capture, king (+ castling), en-passant
+     */
+    if (pos->captured != EMPTY) {                 /* captured: restore piece */
+        pos_set_sq(pos, to, pos->captured);
+    } else if (is_castle(move)) {                 /* castle: rook move */
         square_t rookfrom, rookto;
-        if (to > from) {
-            rookfrom = sq_rel(F1, us);
-            rookto = sq_rel(H1, us);
-        } else {
-            rookfrom = sq_rel(D1, us);
-            rookto = sq_rel(A1, us);
+        if (to > from) {                          /* o-o */
+            rookfrom = to - 1;
+            rookto = to + 1;
+        } else {                                  /* o-o-o */
+            rookfrom = to + 1;
+            rookto = to - 2;
         }
         pos_set_sq(pos, rookto, pos->board[rookfrom]);
         pos_clr_sq(pos, rookfrom);
-    } else if (is_enpassant(move)) {              /* restore grabbed pawn */
+    } else if (is_enpassant(move)) {              /* e.p.: restore grabbed pawn */
         square_t grabbed = to + up;
         pos_set_sq(pos, grabbed, MAKE_PIECE(PAWN, them));
     }
 
+    /* do this always, cheaper than test on K move */
+    pos->king[us] = ctz64(pos->bb[us][KING]);
+    //if (PIECE(piece) == KING)
+    //    pos->king[us] = from;
+
     pos->state = *state;                          /* restore irreversible changes */
     pos->turn = us;
     return pos;
@@ -284,7 +296,7 @@ pos_t *move_do_alt(pos_t *pos, const move_t move, state_t *state)
     }
 
     key ^= zobrist_pieces[piece][from] ^ zobrist_pieces[new_piece][to];
-    pos_clr_sq(pos, from);                        /* clear "from" and set "to" */
+    pos_clr_sq(pos, from);
     pos_set_sq(pos, to, new_piece);
 
     if (ptype == KING)

src/move-do.h

@@ -14,8 +14,11 @@
 #ifndef MOVE_DO_H
 #define MOVE_DO_H
 
+#include "chessdefs.h"
 #include "position.h"
 
+extern castle_rights_t sq_castle[64];             /* to adjust castling rights */
+
 pos_t *move_do(pos_t *pos, const move_t move, state_t *state);
 pos_t *move_undo(pos_t *pos, const move_t move, const state_t *state);
 

src/move-gen.c

@@ -480,3 +480,18 @@ finish:
     return movelist;
     //return movelist->nmoves = moves - movelist->move;
 }
+
+/**
+ * pos_gen_legal() - generate position legal moves
+ * @pos: position
+ * @movelist: &movelist_t array to store moves
+ *
+ * Generate all @pos legal moves for player-to-move.
+ * @movelist is filled with the moves.
+ *
+ * @Return: movelist
+ */
+movelist_t *pos_gen_legal(pos_t *pos, movelist_t *movelist)
+{
+    return pos_legal(pos, pos_gen_pseudo(pos, movelist));
+}

src/move-gen.h

@@ -27,5 +27,6 @@ movelist_t *pos_legal_dup(const pos_t *pos, movelist_t *pseudo, movelist_t *lega
 movelist_t *pos_legal(const pos_t *pos, movelist_t *list);
 
 movelist_t *pos_gen_pseudo(pos_t *pos, movelist_t *movelist);
+movelist_t *pos_gen_legal(pos_t *pos, movelist_t *movelist);
 
 #endif  /* MOVEGEN_H */

src/perft.c

@@ -0,0 +1,131 @@
+/* perft.c - perft functions.
+ *
+ * Copyright (C) 2023-2024 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#include <stdio.h>
+
+#include <brlib.h>
+
+#include "perft.h"
+#include "move-gen.h"
+#include "move-do.h"
+
+/**
+ * perft() - Perform perft on position
+ * @pos:    &position to search
+ * @depth:  Wanted depth.
+ * @ply:    current perft depth level (root = 1)
+ * @divide: output total for 1st level moves.
+ *
+ * Run perft on a position. This function displays the available moves at @depth
+ * level for each possible first move, and the total of moves.
+ *
+ * This version uses the algorithm:
+ *    if last depth
+ *      return 1;
+ *    gen legal moves
+ *    loop for legal move
+ *      do-move
+ *      perft (depth -1)
+ *      undo-move
+ *
+ * @return: total moves found at @depth level.
+ */
+u64 perft(pos_t *pos, int depth, int ply, bool divide)
+{
+    u64 subnodes = 0, nodes = 0;
+    movelist_t movelist;
+    move_t *move, *last;
+    state_t state;
+
+    pos_set_checkers_pinners_blockers(pos);
+
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+    last = movelist.move + movelist.nmoves;
+    for (move = movelist.move; move < last; ++move) {
+        if (depth == 1) {
+            subnodes = 1;
+        } else {
+            move_do(pos, *move, &state);
+            if (depth == 2) {
+                movelist_t movelist2;
+                pos_set_checkers_pinners_blockers(pos);
+                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
+            } else if (ply >= 3) {
+                hentry_t *entry = tt_probe_perft(pos->key, depth);
+                if (entry != TT_MISS) {
+                    subnodes = HASH_PERFT_VAL(entry->data);
+                } else {
+                    subnodes = perft(pos, depth - 1, ply + 1, divide);
+                    tt_store_perft(pos->key, depth, subnodes);
+                }
+            } else {
+                subnodes = perft(pos, depth - 1, ply + 1, divide);
+            }
+            move_undo(pos, *move, &state);
+        }
+        nodes += subnodes;
+        if (ply == 1 && divide) {
+            char movestr[8];
+            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
+        }
+    }
+
+    return nodes;
+}
+
+/**
+ * perft_alt() - Perform perft on position, experimental version.
+ * @pos:    &position to search
+ * @depth:  Wanted depth.
+ * @ply:    current perft depth level (root = 1)
+ * @divide: output total for 1st level moves.
+ *
+ * Run perft on a position. This function displays the available moves at @depth
+ * level for each possible first move, and the total of moves.
+ *
+ * @return: total moves found at @depth level.
+ */
+u64 perft_alt(pos_t *pos, int depth, int ply, bool divide)
+{
+    u64 subnodes = 0, nodes = 0;
+    movelist_t movelist;
+    move_t *move, *last;
+    state_t state;
+
+    pos_set_checkers_pinners_blockers(pos);
+
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+    last = movelist.move + movelist.nmoves;
+    for (move = movelist.move; move < last; ++move) {
+        if (depth == 1) {
+            subnodes = 1;
+        } else {
+            move_do_alt(pos, *move, &state);
+            if (depth == 2) {
+                movelist_t movelist2;
+                pos_set_checkers_pinners_blockers(pos);
+                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
+            } else {
+                subnodes = perft_alt(pos, depth - 1, ply + 1, divide);
+            }
+            move_undo_alt(pos, *move, &state);
+        }
+        nodes += subnodes;
+        if (ply == 1 && divide) {
+            char movestr[8];
+            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
+        }
+    }
+
+    return nodes;
+}

src/perft.h

@@ -0,0 +1,22 @@
+/* perft.h.h - perft.
+ *
+ * Copyright (C) 2021-2024 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef PERFT_H
+#define PERFT_H
+
+#include "position.h"
+
+u64 perft(pos_t *pos, int depth, int ply, bool output);
+u64 perft_alt(pos_t *pos, int depth, int ply, bool output);
+
+#endif  /* PERFT_H */

src/piece.h

@@ -47,6 +47,7 @@ enum __piece_e {
     PIECE_NB
 };
 typedef u8  piece_t;
+
 /* default values for midgame, endgame
  */
 #define E_VAL_MID    0
@@ -103,15 +104,14 @@ extern const char pieces_str[6+6+1];              /* to search from fen/user inp
 #define SET_BLACK(p)      (piece_t)((p) |= MASK_COLOR)
 #define SET_COLOR(p, c)   (piece_t)(!(c)? SET_WHITE(p): SET_BLACK(p))
 
-static __inline s16 piece_midval(piece_type_t pt)
+static __inline eval_t piece_midval(piece_type_t pt)
 {
     return piece_details[pt].mid_value;
 }
-static __inline s16 piece_endval(piece_type_t pt)
+static __inline eval_t piece_endval(piece_type_t pt)
 {
-    return piece_details[pt].mid_value;
+    return piece_details[pt].end_value;
 }
-#define piece_val(pt) piece_midval(pt)
 
 bool piece_ok(piece_t p);
 

src/position.c

@@ -100,31 +100,14 @@ pos_t *pos_clear(pos_t *pos)
 #   ifdef DEBUG_POS
     printf("size(pos_board=%lu elt=%lu\n", sizeof(pos->board), sizeof(int));
 #   endif
-    pos->node_count = 0;
-    pos->turn = WHITE;
+    memset(pos, 0, sizeof (pos_t));
 
-    /* move_do/undo position state */
-    pos->key = 0;
+    /* non-zero values */
     pos->en_passant = SQUARE_NONE;
-    pos->castle = 0;
-    pos->clock_50 = 0;
-    pos->plycount = 0;
     pos->move = MOVE_NONE;
-    pos->captured = NO_PIECE;
 
-    for (square_t sq = A1; sq <= H8; ++sq)
-        pos->board[sq] = EMPTY;
-
-    for (color_t color = WHITE; color <= BLACK; ++color) {
-        for (piece_type_t piece = 0; piece <= KING; ++piece)
-            pos->bb[color][piece] = 0;
-        //pos->controlled[color] = 0;
-        pos->king[color] = SQUARE_NONE;
-    }
-
-    pos->checkers = 0;
-    pos->pinners = 0;
-    pos->blockers = 0;
+    pos->king[WHITE] = SQUARE_NONE;
+    pos->king[BLACK] = SQUARE_NONE;
 
     return pos;
 }

src/position.h

@@ -88,8 +88,8 @@ static __always_inline void pos_set_sq(pos_t *pos, square_t square, piece_t piec
     bug_on(pos->board[square] != EMPTY);
 
     pos->board[square] = piece;
-    pos->bb[color][type] |= BIT(square);
-    pos->bb[color][ALL_PIECES] |= BIT(square);
+    pos->bb[color][type] ^= BIT(square);
+    pos->bb[color][ALL_PIECES] ^= BIT(square);
     //if (type == KING)
     //    pos->king[color] = square;
 
@@ -114,12 +114,38 @@ static __always_inline void pos_clr_sq(pos_t *pos, square_t square)
     //pos->key ^= zobrist_pieces[piece][square];
 
     pos->board[square] = EMPTY;
-    pos->bb[color][type] &= ~BIT(square);
-    pos->bb[color][ALL_PIECES] &= ~BIT(square);
+    pos->bb[color][type] ^= BIT(square);
+    pos->bb[color][ALL_PIECES] ^= BIT(square);
     //if (type == KING)
     //    pos->king[color] = SQUARE_NONE;
 }
 
+/**
+ * pos_mv_sq - move a piece from a square to another one.
+ * @pos: position
+ * @from: source square
+ * @to: dest square
+ *
+ * Both position board and bitboards are modified.
+ * This function is equivalent to:
+ *      pos_set_sq(pos, to, pos->board[from]);
+ *      pos_clr_sq(pos, from);
+ */
+static __always_inline void pos_mv_sq(pos_t *pos, square_t from, square_t to)
+{
+    piece_t pc = pos->board[from];
+    piece_type_t pt = PIECE(pc);
+    color_t color = COLOR(pc);
+    bitboard_t bb_squares = BIT(from) | BIT(to);
+
+    bug_on(pc == EMPTY || pos->board[to] != EMPTY);
+
+    pos->board[from] = EMPTY;
+    pos->board[to] = pc;
+    pos->bb[color][pt] ^= bb_squares;
+    pos->bb[color][ALL_PIECES] ^= bb_squares;
+}
+
 /**
  * pos_occ() - get position occupation (all pieces)
  * @pos: position

src/search.c

@@ -1,4 +1,4 @@
-/* search.c - perft + search.
+/* search.c - search for perfect move.
  *
  * Copyright (C) 2023-2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -21,117 +21,6 @@
 #include "search.h"
 #include "attack.h"
 
-/**
- * perft() - Perform perft on position
- * @pos:    &position to search
- * @depth:  Wanted depth.
- * @ply:    current perft depth level (root = 1)
- * @divide: output total for 1st level moves.
- *
- * Run perft on a position. This function displays the available moves at @depth
- * level for each possible first move, and the total of moves.
- *
- * This version uses the algorithm:
- *    if last depth
- *      return 1;
- *    gen legal moves
- *    loop for legal move
- *      do-move
- *      perft (depth -1)
- *      undo-move
- *
- * @return: total moves found at @depth level.
- */
-u64 perft(pos_t *pos, int depth, int ply, bool divide)
-{
-    u64 subnodes = 0, nodes = 0;
-    movelist_t movelist;
-    move_t *move, *last;
-    state_t state;
-
-    pos_set_checkers_pinners_blockers(pos);
-
-    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
-    last = movelist.move + movelist.nmoves;
-    for (move = movelist.move; move < last; ++move) {
-        if (depth == 1) {
-            subnodes = 1;
-        } else {
-            move_do(pos, *move, &state);
-            if (depth == 2) {
-                movelist_t movelist2;
-                pos_set_checkers_pinners_blockers(pos);
-                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
-            } else if (ply >= 3) {
-                hentry_t *entry = tt_probe_perft(pos->key, depth);
-                if (entry != TT_MISS) {
-                    subnodes = HASH_PERFT_VAL(entry->data);
-                } else {
-                    subnodes = perft(pos, depth - 1, ply + 1, divide);
-                    tt_store_perft(pos->key, depth, subnodes);
-                }
-            } else {
-                subnodes = perft(pos, depth - 1, ply + 1, divide);
-            }
-            move_undo(pos, *move, &state);
-        }
-        nodes += subnodes;
-        if (ply == 1 && divide) {
-            char movestr[8];
-            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
-        }
-    }
-
-    return nodes;
-}
-
-/**
- * perft_alt() - Perform perft on position, experimental version.
- * @pos:    &position to search
- * @depth:  Wanted depth.
- * @ply:    current perft depth level (root = 1)
- * @divide: output total for 1st level moves.
- *
- * Run perft on a position. This function displays the available moves at @depth
- * level for each possible first move, and the total of moves.
- *
- * @return: total moves found at @depth level.
- */
-u64 perft_alt(pos_t *pos, int depth, int ply, bool divide)
-{
-    u64 subnodes = 0, nodes = 0;
-    movelist_t movelist;
-    move_t *move, *last;
-    state_t state;
-
-    pos_set_checkers_pinners_blockers(pos);
-
-    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
-    last = movelist.move + movelist.nmoves;
-    for (move = movelist.move; move < last; ++move) {
-        if (depth == 1) {
-            subnodes = 1;
-        } else {
-            move_do_alt(pos, *move, &state);
-            if (depth == 2) {
-                movelist_t movelist2;
-                pos_set_checkers_pinners_blockers(pos);
-                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
-            } else {
-                subnodes = perft_alt(pos, depth - 1, ply + 1, divide);
-            }
-            move_undo_alt(pos, *move, &state);
-        }
-        nodes += subnodes;
-        if (ply == 1 && divide) {
-            char movestr[8];
-            printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
-        }
-    }
-
-    return nodes;
-}
-
 /**
  * negamax() - search position negamax.
  * @pos: &position to search

src/search.h

@@ -19,7 +19,4 @@
 //eval_t negamax(pos_t *pos, int depth, int color);
 //eval_t pvs(pos_t *pos, int depth, int alpha, int beta, int color);
 
-u64 perft(pos_t *pos, int depth, int ply, bool output);
-u64 perft_alt(pos_t *pos, int depth, int ply, bool output);
-
 #endif  /* SEARCH_H */

src/thread.c

@@ -0,0 +1,70 @@
+/* thread.c - thread management.
+ *
+ * Copyright (C) 2024 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#include <stdio.h>
+
+#include <brlib.h>
+#include <pthread.h>
+#include <poll.h>
+#include <sys/socket.h>
+
+#include "thread.h"
+
+/* Still have to decide: thread or process ?
+ *
+ */
+thread_pool_t threadpool;
+
+
+/**
+ * thrd_create - initialize thrd.
+ */
+int thrd_create(__unused int num)
+{
+    int fd[2];
+    /* shall we make a communication channel via a pipe or socket ? */
+    int __unused ret = socketpair(AF_LOCAL, SOCK_SEQPACKET, PF_LOCAL, fd);
+    return 1;
+}
+
+/**
+ * thread_init - initialize thread pool.
+ */
+int thread_init(int nb)
+{
+    nb = clamp(nb, MIN_THRDS, MAX_THRDS);
+
+    /* stop unwanted threads, always keep 1 */
+    for (int i = nb + 1; i < threadpool.nb; ++i) {
+        printf("stopping thread %d - status = \n", i);
+        threadpool.thread[i].cmd = THRD_DO_QUIT;
+    }
+    for (int i = threadpool.nb; i < nb; ++i) {
+        printf("creating thread %d - status = \n", i);
+        thrd_create(i);
+
+    }
+
+    return nb;
+}
+
+/*
+  communication:
+  main thread -> thread
+           commands via memory
+  thread -> main thread
+           status via memory
+           output via pipe/socket
+  thread output will be output/filtered by main thread
+
+ */

src/thread.h

@@ -0,0 +1,55 @@
+/* thread.h - thread management.
+ *
+ * Copyright (C) 2021-2024 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef THREAD_H
+#define THREAD_H
+
+#include <pthread.h>
+
+#include <brlib.h>
+
+#include "position.h"
+
+#define MIN_THRDS 1
+#define MAX_THRDS 16
+
+typedef enum {
+    THRD_DEAD,
+    THRD_IDLE,
+    THRD_WORKING,
+} thread_status_t;
+
+typedef enum {
+    /* main thread to subs */
+    THRD_DO_SEARCH,
+    THRD_DO_STOP,
+    THRD_DO_QUIT,
+} thread_cmd_t;
+
+typedef struct {
+    int id;
+    thread_status_t status;
+    thread_cmd_t cmd;
+    int fd[2];
+    pos_t pos;
+} thread_t;
+
+typedef struct {
+    int nb;
+    thread_t thread[MAX_THRDS + 1];
+} thread_pool_t;
+
+int thrd_create(__unused int num);
+int thread_init(int nb);
+
+#endif  /* THREAD_H */

src/uci.c

@@ -1,6 +1,6 @@
 /* uci.c - uci protocol
  *
- * Copyright (C) 2024 Bruno Raoult ("br")
+ * Copyright (C) 2021-2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
  * Some rights reserved. See COPYING.
  *
@@ -11,42 +11,44 @@
  *
  */
 
-
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
-#include <ctype.h>
 #include <unistd.h>
+#include <ctype.h>
 
 #include <brlib.h>
 
 #include "chessdefs.h"
+#include "util.h"
 #include "position.h"
-#include "uci.h"
 #include "hist.h"
 #include "fen.h"
 #include "move-gen.h"
 #include "move-do.h"
 #include "search.h"
+#include "perft.h"
+#include "eval-defs.h"
+#include "uci.h"
 
 struct command {
-    char *name;                                   /* User printable name */
+    char *name;                                   /* command name */
     int (*func)(pos_t *, char *);                 /* function doing the job */
     char *doc;                                    /* function doc */
 };
 
 int execute_line (pos_t *, struct command *, char *);
-
 struct command *find_command (char *);
-int string_trim (char *str);
 
-/* The names of functions that actually do the manipulation. */
+/* The names of functions that actually do the stuff.
+ */
 
 /* standard UCI commands */
 int do_ucinewgame(pos_t *, char *);
 int do_uci(pos_t *, char *);
 int do_isready(pos_t *, char *);
+int do_quit(pos_t *, char *);
 
+int do_setoption(pos_t *, char *);
 int do_position(pos_t *, char *);
 
 /* commands *NOT* in UCI standard */
@@ -56,54 +58,25 @@ int do_perft(pos_t *, char *);
 
 int do_hist(pos_t *, char *);
 int do_help(pos_t *, char *);
-int do_quit(pos_t *, char *);
 
 struct command commands[] = {
-    { "help",       do_help, "(not UCI) This help" },
-    { "?",          do_help, "(not UCI) This help" },
     { "quit",       do_quit, "Quit" },
-
     { "uci",        do_uci, "" },
     { "ucinewgame", do_ucinewgame, "" },
     { "isready",    do_isready, "" },
-
+    { "setoption",  do_setoption, ""},
     { "position",   do_position, "position startpos|fen [moves ...]" },
 
     { "perft",      do_perft, "(not UCI) perft [divide] [alt] depth" },
     { "moves",      do_moves, "(not UCI) moves ..." },
     { "diagram",    do_diagram, "(not UCI) print current position diagram" },
     { "hist",       do_hist, "(not UCI) print history states" },
+    { "help",       do_help, "(not UCI) This help" },
+    { "?",          do_help, "(not UCI) This help" },
 
     { NULL, (int(*)()) NULL, NULL }
 };
 
-static int done = 0;
-
-int uci(pos_t *pos)
-{
-    char *str = NULL, *saveptr, *token, *args;
-    int len;
-    size_t lenstr = 0;
-    struct command *command;
-
-    while (!done && getline(&str, &lenstr, stdin) >= 0) {
-        if (!(len = string_trim(str)))
-            continue;
-        token = strtok_r(str, " ", &saveptr);
-        if (! (command= find_command(token))) {
-            fprintf(stderr, "Unknown [%s] command. Try 'help'.\n", token);
-            continue;
-        }
-        args = strtok_r(NULL, "", &saveptr);
-        execute_line(pos, command, args);
-    }
-
-    if (str)
-        free(str);
-
-    return 0;
-}
-
 /* Execute a command line. */
 int execute_line(pos_t *pos, struct command *command, char *args)
 {
@@ -115,7 +88,7 @@ int execute_line(pos_t *pos, struct command *command, char *args)
  * @name: &command string
  *
  * Look up NAME as the name of a command, and return a pointer to that
- *   command.  Return a NULL pointer if NAME isn't a command name.
+ * command.  Return a NULL pointer if NAME isn't a command name.
  */
 struct command *find_command(char *name)
 {
@@ -252,8 +225,37 @@ int do_uci(__unused pos_t *pos, __unused char *arg)
 {
     printf("id name brchess " VERSION "\n");
     printf("id author Bruno Raoult\n");
-    printf("option option name Hash type spin default %d min %d max %d\n",
+    printf("option name Hash type spin default %d min %d max %d\n",
            hash_tt.mb, HASH_SIZE_MIN, HASH_SIZE_MAX);
+
+    if (PST_NB > 1) {
+        printf("option name pst type combo default %s",
+               pst_name(pst_current));
+        for (int i = 0; i < PST_NB; ++i)
+            printf(" var %s", pst_name(i));
+    }
+    printf("\n");
+    for (int var = 0; var < EV_PARAMS_NB; ++var) {
+        if (param_setable(var)) {
+            int ptyp = param_type(var);
+            int pmin = param_min(var);
+            int pmax = param_max(var);
+            int pval = parameters[var];
+
+            printf("option name %s ", param_name(var));
+            switch(ptyp) {
+                case PAR_BTN:
+                    printf("type button\n");
+                    break;
+                case PAR_CHK:
+                    printf("type check default %s\n", pval? "true": "false");
+                    break;
+                case PAR_SPN:
+                    printf("type spin default %d min %d max %d\n", pval, pmin, pmax);
+                    break;
+            };
+        }
+    }
     printf("uciok\n");
     return 1;
 }
@@ -264,6 +266,72 @@ int do_isready(__unused pos_t *pos, __unused char *arg)
     return 1;
 }
 
+int do_setoption(__unused pos_t *pos, __unused char *arg)
+{
+    char *name, *value = NULL;
+
+    if (str_token(arg, "name") != arg)
+        return 1;
+    if (!(name = str_skip_word(arg)))
+        return 1;
+    /* at this point, we got a valid parameter name */
+    value = str_token(name, "value");             /* put '\0' at name end */
+    if (value) {
+        value = str_skip_word(value);
+        if (!value)
+            return 1;
+    }
+    if (str_eq_case(name, "hash") && value) {
+        tt_create(atoi(value));
+    } else if (str_eq_case(name, "pst")) {
+        pst_set(value);
+    } else {
+        int var = param_find_name(name);
+        if (var < 0) {
+            printf("wrong parameter '%s'\n", name);
+            return 1;
+        }
+        char *pname = param_name(var);
+        printf("found param <%s> = %d\n", pname, var);
+        if (param_setable(var)) {
+            int ptyp = param_min(var);
+            int pmin = param_min(var);
+            int pmax = param_max(var);
+            int pval;
+
+            switch(ptyp) {
+                case PAR_BTN:
+                    bug_on (value);
+                    printf("do button '%s'\n", pname);
+                    break;
+                case PAR_CHK:
+                    bug_on (!value);
+                    if (str_eq_case(value, "true"))
+                        pval = 1;
+                    else if (str_eq_case(value, "false"))
+                        pval = 0;
+                    else {
+                        printf("wrong value '%s' to '%s' boolean parameter\n",
+                               value, pname);
+                        return 1;
+                    }
+                    printf("set '%s' to %s\n", pname, pval? "true": "false");
+                    param_set(var, pval);
+                    break;
+                case PAR_SPN:
+                    bug_on (!value);
+                    pval = clamp(atoi(value), pmin, pmax);
+                    printf("set '%s' to %d\n", param_name(var), pval);
+                    param_set(var, pval);
+                    break;
+            }
+        }
+    }
+
+    return 0;
+}
+
+
 int do_position(pos_t *pos, char *arg)
 {
     char *saveptr, *token, *fen, *moves;
@@ -271,9 +339,7 @@ int do_position(pos_t *pos, char *arg)
     hist_init();
 
     /* separate "moves" section */
-    if ((moves = strstr(arg, "moves"))) {
-        *(moves - 1) = 0;
-    }
+    moves = str_token(arg, "moves");
     saveptr = NULL;
     token = strtok_r(arg, " ", &saveptr);
     if (!strcmp(token, "startpos")) {
@@ -370,7 +436,6 @@ int do_perft(__unused pos_t *pos, __unused char *arg)
     return 1;
 }
 
-
 int do_hist(__unused pos_t *pos, __unused char *arg)
 {
     hist_static_print();
@@ -387,11 +452,6 @@ int do_help(__unused pos_t *pos, __unused char *arg)
     return 0;
 }
 
-int do_quit(__unused pos_t *pos, __unused char *arg)
-{
-    return done = 1;
-}
-
 /*
  * int do_depth(__unused pos_t *pos, char *arg)
  * {
@@ -448,45 +508,35 @@ int do_quit(__unused pos_t *pos, __unused char *arg)
  * }
  */
 
-/**
- * string_trim - cleanup (trim) blank characters in string.
- * @str: &string to clean
- *
- * str is cleaned and packed with the following rules:
- * - Leading and trailing blank characters are removed.
- * - consecutive blank characters are replaced by one space.
- * - non printable characters are removed.
- *
- * "blank" means characters as understood by isspace(3): space, form-feed ('\f'),
- * newline ('\n'), carriage return ('\r'), horizontal tab  ('\t'), and vertical
- * tab ('\v').
- *
- * @return: new @str len.
- */
-int string_trim(char *str)
-{
-    char *to = str, *from = str;
-    int state = 1;
 
-    while (*from) {
-        switch (state) {
-            case 1:                               /* blanks */
-                while (*from && isspace(*from))
-                    from++;
-                state = 0;
-                break;
-            case 0:                               /* token */
-                while (*from && !isspace(*from)) {
-                    if (isprint(*from))
-                        *to++ = *from;
-                    from++;
-                }
-                *to++ = ' ';
-                state = 1;
-        }
-    }
-    if (to > str)
-        to--;
-    *to = 0;
-    return to - str;
+static int done = 0;
+
+int do_quit(__unused pos_t *pos, __unused char *arg)
+{
+    return done = 1;
+}
+
+int uci(pos_t *pos)
+{
+    char *str = NULL, *saveptr, *token, *args;
+    size_t lenstr = 0;
+    struct command *command;
+
+    while (!done && getline(&str, &lenstr, stdin) >= 0) {
+        str = str_trim(str);
+        if (! *str)
+            continue;
+        token = strtok_r(str, " ", &saveptr);
+        if (! (command = find_command(token))) {
+            fprintf(stderr, "Unknown [%s] command. Try 'help'.\n", token);
+            continue;
+        }
+        args = strtok_r(NULL, "", &saveptr);
+        execute_line(pos, command, args);
+    }
+
+    if (str)
+        free(str);
+
+    return 0;
 }

src/uci.h

@@ -1,4 +1,4 @@
-/* util.h - various util functions.
+/* uci.h - main loop.
  *
  * Copyright (C) 2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -11,8 +11,11 @@
  *
  */
 
-#ifndef _UTIL_H
-#define _UTIL_H
+#ifndef UCI_H
+#define UCI_H
 
+#include "position.h"
 
-#endif  /* UTIL_H */
+int uci(pos_t *pos);
+
+#endif  /* UCI_H */

src/util.c

@@ -1,4 +1,4 @@
-/* misc.c - generic/catchall functions.
+/* util.c - generic/catchall functions.
  *
  * Copyright (C) 2024 Bruno Raoult ("br")
  * Licensed under the GNU General Public License v3.0 or later.
@@ -11,12 +11,15 @@
  *
  */
 
-#include <time.h>
-#include <stdlib.h>
+//#include <time.h>
+//#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
 
 #include <bug.h>
 
 #include "chessdefs.h"
+#include "util.h"
 
 /*
  * 1 sec      = 1000 millisec
@@ -34,10 +37,6 @@
 
 #define MICRO_IN_MILLI 1000ll
 
-//#define NANO_IN_MILLI  1000000ll                         /* nanosecond in millisecond */
-//#define NANO_IN_SEC    (NANOS_IN_MS * MS_IN_SEC)
-
-
 /**
  * clock_start - start or restart a clock.
  * @clock: &mclock_t clock
@@ -150,3 +149,126 @@ u64 rand64(void)
     rand_seed ^= rand_seed >> 27;
     return rand_seed * 0x2545f4914f6cdd1dull;
 }
+
+/**
+ * str_eq_case - test if two strings are equal ignoring case
+ * @str1: string1
+ * @str2: string2
+ *
+ * Compare @str1 and @str2 byte-by-byte, ignoring case.
+ *
+ * @return: true is equal, false otherwise.
+ */
+bool str_eq_case(char *str1, char *str2)
+{
+    uchar *s1 = (uchar *) str1;
+    uchar *s2 = (uchar *) str2;
+
+    for (; *s1 && *s2; ++s1, ++s2) {
+        if (tolower(*s1) != tolower(*s2))
+            break;
+    }
+    //printf("d=%lu *s1=%d *s2=%d\n", s1 - (uchar *) str1, *s1, *s2);
+    return *s2 == *s1;
+}
+
+/**
+ * str_trim - cleanup (trim) blank characters in string.
+ * @str: &string to clean
+ *
+ * str is cleaned and packed with the following rules:
+ * - Leading and trailing blank characters are removed.
+ * - consecutive blank characters are replaced by one space.
+ * - non printable characters are removed.
+ *
+ * "blank" means characters as understood by isspace(3): space, form-feed ('\f'),
+ * newline ('\n'), carriage return ('\r'), horizontal tab  ('\t'), and vertical
+ * tab ('\v').
+ *
+ * @return: new @str len.
+ */
+char *str_trim(char *str)
+{
+    char *to = str, *from = str;
+    int state = 1;
+
+    bug_on(!str);
+    while (*from) {
+        switch (state) {
+            case 1:                               /* blanks */
+                while (*from && isspace(*from))
+                    from++;
+                state = 0;
+                break;
+            case 0:                               /* token */
+                while (*from && !isspace(*from)) {
+                    if (isprint(*from))
+                        *to++ = *from;
+                    from++;
+                }
+                *to++ = ' ';
+                state = 1;
+        }
+    }
+    if (to > str)
+        to--;
+    *to = 0;
+    return str;
+}
+
+/**
+ * str_token - split a string from next token.
+ * @str:   string to search
+ * @token: token to look for
+ *
+ * Look for token @token in string @str, and if found, split @str just before it.
+ * A token is a string delimited by one space character. However, it may contain
+ * space characters itself.
+ * @str should normally be normalized with @str_trim(), so that all consecutive
+ * blank characters are replaced by one, and leading/trailing ones removed.
+ *
+ * @return: @token address if found, NULL otherwise.
+ */
+char *str_token(char *str, const char *token)
+{
+    int len = strlen(token);
+    char *found = str;
+
+    bug_on(!str || !token);
+    if (!*token)                                  /* nothing to search */
+        return str;
+
+    while (found && *found) {
+        //printf("trying pos=%ld\n", found - str);
+        found = strstr(found, token);
+        if (found) {
+            if (!found[len] || isspace(found[len]))
+                break;
+            found = strchr(found, ' ') + 1;
+            //printf("new pos=%ld\n", found - str);
+        }
+    }
+    if (found > str)                              /* split string */
+        *(found - 1) = 0;
+    return found;
+}
+
+/**
+ * str_skip_word - find next word in a string.
+ * @str:   input string
+ *
+ * skip current word and following blank char.
+ * @str must be normalized with @str_trim(), so that all consecutive blank
+ * characters are already replaced by one, and leading/trailing ones removed.
+ * Note that 'word' means any sequence of non-space character.
+ *
+ * @str is not modified.
+ *
+ * @return: next word if found, NULL otherwise.
+ */
+char *str_skip_word(char *str)
+{
+    bug_on(!str);
+    str = strchr(str, ' ');
+    return str? str + 1: NULL;
+}

src/util.h

@@ -0,0 +1,61 @@
+/* util.h - various util functions.
+ *
+ * Copyright (C) 2024 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef _UTIL_H
+#define _UTIL_H
+
+#include <brlib.h>
+
+#include <time.h>
+
+typedef struct mclock {
+    clockid_t clocktype;
+    ulong elapsed_l;
+    double elapsed_f;
+    struct timespec start;
+} mclock_t;
+
+#define CLOCK_WALL    CLOCK_REALTIME
+#define CLOCK_SYSTEM  CLOCK_MONOTONIC_RAW
+#define CLOCK_PROCESS CLOCK_PROCESS_CPUTIME_ID
+#define CLOCK_THREAD  CLOCK_THREAD_CPUTIME_ID
+
+/**
+ * CLOCK_DEFINE - define a clock type.
+ * @name: clock name
+ * @type: clock type
+ *
+ * This macro is equivalent to:
+ *   mclock_t name;
+ *   clock_init(&name, type);
+ */
+#define CLOCK_DEFINE(name, type) struct mclock name = { .clocktype = type }
+
+void clock_init(mclock_t *clock, clockid_t type);
+void clock_start(mclock_t *clock);
+s64 clock_elapsed_μs(mclock_t *clock);
+s64 clock_elapsed_ms(mclock_t *clock);
+double clock_elapsed_sec(mclock_t *clock);
+
+#define RAND_SEED_DEFAULT U64(0xb0d1ccea)
+
+void rand_init(u64 seed);
+u64 rand64(void);
+
+
+bool str_eq_case(char *str1, char *str2);
+char *str_trim(char *str);
+char *str_token(char *str, const char *token);
+char *str_skip_word(char *str);
+
+#endif  /* UTIL_H */

test/common-test.h

@@ -198,6 +198,10 @@ struct fentest {
     /*****************************************************
      * tests from talkchess                              *
      *****************************************************/
+    { __LINE__, FEN | MOVEGEN | MOVEDO | PERFT,
+      "https://talkchess.com/viewtopic.php?t=21343",
+      "8/k7/3p4/p2P1p2/P2P1P2/8/8/K7 w - - 0 1"
+    },
     { __LINE__, FEN | MOVEGEN | MOVEDO | PERFT,
       "https://www.talkchess.com/forum3/viewtopic.php?f=7&t=71379",
       "8/6kR/8/8/8/bq6/1rqqqqqq/K1nqnbrq b - - 0 1"
@@ -447,7 +451,12 @@ struct fentest {
 
 static int fentest_cur = -1;
 
-static char *next_fen(uint module)
+static __unused void restart_fen(void)
+{
+    fentest_cur = -1;
+}
+
+static __unused char *next_fen(uint module)
 {
     fentest_cur++;
 

test/movedo-test.c

@@ -52,8 +52,8 @@ int main(int __unused ac, __unused char**av)
         for (move = movelist.move; move < last; ++move) {
             //pos_print(pos);
             //printf("i=%d j=%d  turn=%d move=[%s]\n", i, j, pos->turn,
-            //       move_str(movebuf, move, 0));
-            //move_p
+            //       move_to_str(movebuf, *move, 0));
+
             move_do(pos, *move, &state);
             //pos_print(pos);
             //fflush(stdout);
@@ -67,6 +67,7 @@ int main(int __unused ac, __unused char**av)
             move_undo(pos, *move, &state);
             pos->state = state;
             if (!pos_ok(pos, false)) {
+                //pos_print(pos);
                 printf("*** fen %d [%s] move %d [%s] invalid position after move_undo\n",
                        test_line, fen, j, movebuf);
                 exit(0);

test/perft-test.c

@@ -19,12 +19,13 @@
 #include <limits.h>
 
 #include "chessdefs.h"
+#include "util.h"
 #include "fen.h"
 #include "position.h"
 #include "move.h"
 #include "move-do.h"
 #include "move-gen.h"
-#include "search.h"
+#include "perft.h"
 
 #include "common-test.h"
 
@@ -241,7 +242,9 @@ static int usage(char *prg)
     fprintf(stderr, "Usage: %s [-cms][-d depth] [-p version] [-t size:\n", prg);
     fprintf(stderr, "\t-c:         do *not* print FEN comments\n");
     fprintf(stderr, "\t-d depth:   perft depth (default: 6)\n");
+    fprintf(stderr, "\t-l line:    start from 'line' test\n");
     fprintf(stderr, "\t-m:         print moves details\n");
+    fprintf(stderr, "\t-n number:  do 'number' tests (default: all)\n");
     fprintf(stderr, "\t-s:         use Stockfish to validate perft result\n");
     fprintf(stderr, "\t-t size:    Transposition Table size (Mb). Default: 32\n");
     fprintf(stderr,
@@ -251,7 +254,7 @@ static int usage(char *prg)
 
 int main(int ac, char**av)
 {
-    int curtest = 0;
+    int curtest = 0, totalfen = 0;
     u64 sf_count = 0, my_count;
     bool comment = true, sf_run = false, divide = false;
     char *fen;
@@ -261,6 +264,8 @@ int main(int ac, char**av)
     FILE *outfd = NULL;
     s64 ms, lps;
     int opt, depth = 6, run = 3, tt, newtt = HASH_SIZE_DEFAULT;
+    int startline = 1, ntests = INT_MAX;
+
     struct {
         s64 count, countskipped, ms;
         s64 minlps, maxlps;
@@ -272,7 +277,8 @@ int main(int ac, char**av)
         { .minlps = LONG_MAX },
     };
 
-    while ((opt = getopt(ac, av, "cd:mp:st:")) != -1) {
+    printf("Perft " VERSION "\n");
+    while ((opt = getopt(ac, av, "cd:l:mn:p:st:")) != -1) {
         switch (opt) {
             case 'c':
                 comment = false;
@@ -282,9 +288,15 @@ int main(int ac, char**av)
                 if (depth <= 0)
                     depth = 6;
                 break;
+            case 'l':
+                startline = atoi(optarg);
+                break;
             case 'm':
                 divide = true;
                 break;
+            case 'n':
+                ntests = atoi(optarg);
+                break;
             case 'p':
                 run = atoi(optarg);
                 break;
@@ -324,14 +336,23 @@ int main(int ac, char**av)
     if (sf_run)
         outfd = open_stockfish();
 
+    /* count total fen tests we will do */
+    while (next_fen(PERFT | MOVEDO))
+        totalfen++;
+    restart_fen();
+
     CLOCK_DEFINE(clock, CLOCK_MONOTONIC);
     while ((fen = next_fen(PERFT | MOVEDO))) {
+        if (cur_line() < startline)
+            continue;
+        if (curtest >= ntests)
+            break;
         if (!(fenpos = fen2pos(pos, fen))) {
             printf("wrong fen line:%d fen:%s\n\n", cur_line(), fen);
             continue;
         }
         curtest++;
-        printf("test:%d line:%d fen:%s\n", curtest, cur_line(), fen);
+        printf("test:%d/%d line:%d fen:%s\n", curtest, totalfen, cur_line(), fen);
         if (comment)
             printf("\t\"%s\"\n",
                    *cur_comment()? cur_comment(): "no test desc");