add info in pos_print, start perft TT testing

.dir-locals.el

@@ -1,3 +1,3 @@
 ((nil . ((compile-command . (concat "make -C "
                                        (vc-root-dir)
-                                       " -k -j2 testing")))))
+                                       " -k -j4 testing")))))

Makefile

@@ -11,9 +11,9 @@
 #
 
 SHELL     := /bin/bash
-CC        := gcc
+#CC        := gcc
+CC        := gcc-13
 #CC        := clang
-LD        := ld
 BEAR      := bear
 TOUCH     := touch
 RM        := rm
@@ -55,9 +55,9 @@ CPPFILES  := $(SRC:.c=.i) $(TSTSRC:.c=.i)
 ##################################### pre-processor flags
 CPPFLAGS  := -I$(BRINCDIR) -I$(INCDIR)
 
-CPPFLAGS  += -DNDEBUG                                       # assert
-CPPFLAGS  += -DBUG_ON                                       # brlib bug.h
+CPPFLAGS  += -DNDEBUG                                       # assert (unused)
 CPPFLAGS  += -DWARN_ON                                      # brlib bug.h
+CPPFLAGS  += -DBUG_ON                                       # brlib bug.h
 
 #CPPFLAGS  += -DDEBUG                                        # global - unused
 #CPPFLAGS  += -DDEBUG_DEBUG                                  # enable log() functions
@@ -69,16 +69,18 @@ CPPFLAGS  += -DWARN_ON                                      # brlib bug.h
 # fen.c
 #CPPFLAGS  += -DDEBUG_FEN                                    # FEN decoding
 
+# hash.c
+CPPFLAGS  += -DZOBRIST_VERIFY                                # chk zobrist consistency
+
 # attack.c
-#CPPFLAGS  += -DDEBUG_ATTACK_ATTACKERS1                      # sq_attackers details
-CPPFLAGS  += -DDEBUG_ATTACK_ATTACKERS                       # sq_attackers
-CPPFLAGS  += -DDEBUG_ATTACK_PINNERS                         # sq_pinners details
+#CPPFLAGS  += -DDEBUG_ATTACK_ATTACKERS                       # sq_attackers
+#CPPFLAGS  += -DDEBUG_ATTACK_PINNERS                         # sq_pinners details
 
 #CPPFLAGS  += -DDEBUG_EVAL                                   # eval functions
 #CPPFLAGS  += -DDEBUG_PIECE                                  # piece list management
 #CPPFLAGS  += -DDEBUG_SEARCH                                 # move search
 
-CPPFLAGS  += -DDIAGRAM_SYM                                  # diagram with symbols
+CPPFLAGS  += -DDIAGRAM_SYM                                  # UTF8 symbols in diagrams
 
 # remove extraneous spaces (due to spaces before comments)
 CPPFLAGS  := $(strip $(CPPFLAGS))
@@ -89,27 +91,29 @@ CFLAGS    := -std=gnu11
 ### dev OR release
 
 # dev
-# CFLAGS    += -O1
 CFLAGS    += -g                                             # symbols (gdb, perf, etc.)
 CFLAGS    += -ginline-points                                # inlined funcs debug info
+#CFLAGS    += -Og
 # for gprof
 #CFLAGS += -pg
 # Next one may be useful for valgrind (when invalid instructions)
 #CFLAGS += -mno-tbm
 
 # release
-CFLAGS    += -Ofast
+CFLAGS    += -O3
 
 CFLAGS    += -march=native
 CFLAGS    += -flto
+CFLAGS    += -funroll-loops
 CFLAGS    += -Wall
 CFLAGS    += -Wextra
+CFLAGS    += -Wshadow
 CFLAGS    += -Wmissing-declarations
 
 CFLAGS    := $(strip $(CFLAGS))
 
 # development CFLAGS - unused - TODO
-#DEV_CFLAGS := -O1
+#DEV_CFLAGS := -Og
 #DEV_CFLAGS += -g
 
 # release CFLAGS - unused - TODO
@@ -130,6 +134,38 @@ DEPFLAGS   = -MMD -MP -MF $(DEPDIR)/$*.d
 ALL_CFLAGS  = $(DEPFLAGS) $(CPPFLAGS) $(CFLAGS)
 ALL_LDFLAGS = $(LDFLAGS) $(LIBS)
 
+##################################### Multi-targets
+# We can have an issue with Make's "-j" option, in some situations,
+# for example "make -j2 clean testing".
+# See https://stackoverflow.com/a/8496333/3079831
+
+# Check if job server supported:
+ifeq ($(filter jobserver, $(.FEATURES)),)
+# Job server not supported: sub-makes will only start one job unless
+# you specify a higher number here.  Here we use a MS Windows environment
+# variable specifying number of processors.
+JOBSARG := -j $(NUMBER_OF_PROCESSORS)
+else
+# Job server is supported; let GNU Make work as normal.
+JOBSARG :=
+endif
+
+# .FEATURES only works in GNU Make 3.81+.
+# If GNU make is older, assume job server support.
+ifneq ($(firstword $(sort 3.81 $(MAKE_VERSION))),3.81)
+# If you are using GNU Make < 3.81 that does not support job servers, you
+# might want to specify -jN parameter here instead.
+JOBSARG :=
+endif
+
+ifneq ($(words $(MAKECMDGOALS)),1)
+.NOTPARALLEL:
+# The "all" target is required in the list,
+# in case user invokes make with no targets.
+$(sort all $(MAKECMDGOALS)):
+	@$(MAKE) $(JOBSARG) -f $(firstword $(MAKEFILE_LIST)) $@
+else
+
 ##################################### General targets
 .PHONY: all compile clean cleanall
 
@@ -303,16 +339,17 @@ memcheck: targets
 .PHONY: testing test
 
 TEST          := piece-test fen-test bitboard-test movegen-test attack-test
-TEST          += movedo-test perft-test
+TEST          += movedo-test perft-test tt-test
 
 PIECE_OBJS    := piece.o
 FEN_OBJS      := $(PIECE_OBJS) fen.o position.o bitboard.o board.o \
-	hyperbola-quintessence.o attack.o
+	hyperbola-quintessence.o attack.o hash.o init.o
 BB_OBJS       := $(FEN_OBJS)
 MOVEGEN_OBJS  := $(BB_OBJS) move.o move-gen.o
 ATTACK_OBJS   := $(MOVEGEN_OBJS)
-MOVEDO_OBJS   := $(ATTACK_OBJS) move-do.o
-PERFT_OBJS    := $(MOVEDO_OBJS) search.o misc.o
+MOVEDO_OBJS   := $(ATTACK_OBJS) move-do.o misc.o
+PERFT_OBJS    := $(MOVEDO_OBJS) search.o
+TT_OBJS       := $(MOVEDO_OBJS)
 
 TEST          := $(addprefix $(BINDIR)/,$(TEST))
 
@@ -323,6 +360,7 @@ MOVEGEN_OBJS  := $(addprefix $(OBJDIR)/,$(MOVEGEN_OBJS))
 ATTACK_OBJS   := $(addprefix $(OBJDIR)/,$(ATTACK_OBJS))
 MOVEDO_OBJS   := $(addprefix $(OBJDIR)/,$(MOVEDO_OBJS))
 PERFT_OBJS    := $(addprefix $(OBJDIR)/,$(PERFT_OBJS))
+TT_OBJS       := $(addprefix $(OBJDIR)/,$(TT_OBJS))
 
 test:
 	echo TEST=$(TEST)
@@ -358,6 +396,10 @@ bin/perft-test: test/perft-test.c test/common-test.h $(PERFT_OBJS)
 	@echo compiling $@ test executable.
 	@$(CC) $(ALL_CFLAGS) $< $(PERFT_OBJS) $(ALL_LDFLAGS) -o $@
 
+bin/tt-test: test/tt-test.c test/common-test.h $(TT_OBJS)
+	@echo compiling $@ test executable.
+	@$(CC) $(ALL_CFLAGS) $< $(TT_OBJS) $(ALL_LDFLAGS) -o $@
+
 ##################################### Makefile debug
 .PHONY: showflags wft
 
@@ -380,3 +422,6 @@ wtf:
 
 zob:
 	$(CC) $(LDFLAGS) $(CPPFLAGS) $(CFLAGS) $< $(LIBS) src/util.c -o util
+
+##################################### End of multi-targets
+endif

scripts/fetch-all.sh

@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+#
+# Fetch all branches from remotes, and track missing ones.
+#
+# The value of variable ORIGIN is used for repository origin. If
+# not set, the default is "origin".
+
+default_origin=origin
+
+origin=${ORIGIN:-$default_origin}
+
+declare -a local_b
+declare -A alocal_b
+
+# fetch all remotes
+git fetch --all --tags
+
+# get local branches, and build reverse associative array
+readarray -t local_b < <(git for-each-ref --format='%(refname:short)' refs/heads/)
+for ref in "${local_b[@]}"; do
+    alocal_b[$ref]=1
+done
+
+# get "origin" branches
+readarray -t orig_b  < <(git for-each-ref --format='%(refname:short)' \
+                             refs/remotes/"$origin"/)
+
+# find-out missing local branches and track them.
+# bugs:
+#  - We only check local branch existence, not tracking information correctness.
+#  - What about sub-branches ? Like remote/a and remote/a/b not being tracked ?
+for remote_b in "${orig_b[@]}"; do
+    short=${remote_b#"$origin"/};
+    # OR (??): short=${remote_b##*/}
+
+    if ! [[ -v alocal_b[$short] ]]; then
+        printf "local branch %s set to track %s.\n" "$short" "$remote_b"
+        git branch --track "$short" "$remote_b"
+    else
+        printf "skipping %s.\n" "$remote_b"
+    fi
+done
+
+git pull -a

src/attack.c

@@ -42,6 +42,15 @@ bool sq_is_attacked(const pos_t *pos, const bitboard_t occ, const square_t sq, c
 {
     color_t opp = OPPONENT(c);
 
+    /*
+     * return (hyperbola_bishop_moves(occ, sq) & (pos->bb[c][BISHOP] | pos->bb[c][QUEEN])
+     *      || hyperbola_rook_moves(occ, sq) & (pos->bb[c][ROOK] | pos->bb[c][QUEEN])
+     *      || bb_pawn_attacks[opp][sq] & pos->bb[c][PAWN]
+     *      || bb_knight_moves(pos->bb[c][KNIGHT], sq)
+     *      || bb_king_moves(pos->bb[c][KING], sq)
+     *  )
+     */
+
     /* bishop / queen */
     if (hyperbola_bishop_moves(occ, sq) & (pos->bb[c][BISHOP] | pos->bb[c][QUEEN]))
         return true;
@@ -50,14 +59,14 @@ bool sq_is_attacked(const pos_t *pos, const bitboard_t occ, const square_t sq, c
     if (hyperbola_rook_moves(occ, sq) & (pos->bb[c][ROOK] | pos->bb[c][QUEEN]))
         return true;
 
-    /* pawn */
-    if (bb_pawn_attacks[opp][sq] & pos->bb[c][PAWN])
-        return true;
-
     /* knight */
     if (bb_knight_moves(pos->bb[c][KNIGHT], sq))
         return true;
 
+    /* pawn */
+    if (bb_pawn_attacks[opp][sq] & pos->bb[c][PAWN])
+        return true;
+
     /* king */
     if (bb_king_moves(pos->bb[c][KING], sq))
         return true;
@@ -100,35 +109,29 @@ bool is_in_check(const pos_t *pos, const color_t color)
 bitboard_t sq_attackers(const pos_t *pos, const bitboard_t occ, const square_t sq, const color_t c)
 {
     bitboard_t attackers = 0, tmp;
-    bitboard_t sqbb = mask(sq);
-    //bitboard_t occ = pos_occ(pos);
+    bitboard_t sqbb = BIT(sq);
     bitboard_t to;
     color_t opp = OPPONENT(c);
 
     /* pawn */
     to =  pos->bb[c][PAWN];
-    tmp = pawn_shift_upleft(sqbb, opp) & to;
+    tmp = bb_pawns_attacks(sqbb, sq_up(opp)) & to;
     attackers |= tmp;
-#   ifdef DEBUG_ATTACK_ATTACKERS1
-    bb_print("att pawn upleft", tmp);
-#   endif
-    tmp = pawn_shift_upright(sqbb, opp) & to;
-    attackers |= tmp;
-#   ifdef DEBUG_ATTACK_ATTACKERS1
-    bb_print("att pawn upright", tmp);
+#   ifdef DEBUG_ATTACK_ATTACKERS
+    bb_print("att pawn", tmp);
 #   endif
 
     /* knight & king */
     to = pos->bb[c][KNIGHT];
     tmp = bb_knight_moves(to, sq);
     attackers |= tmp;
-#   ifdef DEBUG_ATTACK_ATTACKERS1
+#   ifdef DEBUG_ATTACK_ATTACKERS
     bb_print("att knight", tmp);
 #   endif
     to = pos->bb[c][KING];
     tmp = bb_king_moves(to, sq);
     attackers |= tmp;
-#   ifdef DEBUG_ATTACK_ATTACKERS1
+#   ifdef DEBUG_ATTACK_ATTACKERS
     bb_print("att king", tmp);
 #   endif
 
@@ -136,7 +139,7 @@ bitboard_t sq_attackers(const pos_t *pos, const bitboard_t occ, const square_t s
     to = pos->bb[c][BISHOP] | pos->bb[c][QUEEN];
     tmp = hyperbola_bishop_moves(occ, sq) & to;
     attackers |= tmp;
-#   ifdef DEBUG_ATTACK_ATTACKERS1
+#   ifdef DEBUG_ATTACK_ATTACKERS
     bb_print("att bishop/queen", tmp);
 #   endif
 
@@ -144,10 +147,9 @@ bitboard_t sq_attackers(const pos_t *pos, const bitboard_t occ, const square_t s
     to = pos->bb[c][ROOK] | pos->bb[c][QUEEN];
     tmp = hyperbola_rook_moves(occ, sq) & to;
     attackers |= tmp;
-#   ifdef DEBUG_ATTACK_ATTACKERS1
+#   ifdef DEBUG_ATTACK_ATTACKERS
     bb_print("att rook/queen", tmp);
     bb_print("ATTACKERS", attackers);
-    printf("attackers=%lx\n", attackers);
 #   endif
 
     return attackers;
@@ -178,7 +180,7 @@ bitboard_t sq_pinners(const pos_t *pos, const square_t sq, const color_t color)
         bitboard_t between = bb_between_excl[maybe_pinner][sq];
         /* keep only squares between AND on sq diag/anti */
         if (popcount64(between & lines) == 1)
-            pinners |= mask(maybe_pinner);
+            pinners |= BIT(maybe_pinner);
     }
 
     /* same for rook type */
@@ -187,7 +189,7 @@ bitboard_t sq_pinners(const pos_t *pos, const square_t sq, const color_t color)
     bit_for_each64(maybe_pinner, tmp, attackers) {
         bitboard_t between = bb_between_excl[maybe_pinner][sq];
         if (popcount64(between & lines) == 1)
-            pinners |= mask(maybe_pinner);
+            pinners |= BIT(maybe_pinner);
     }
 #   ifdef DEBUG_ATTACK_ATTACKERS1
     char str[32];

src/bitboard.c

@@ -53,8 +53,8 @@ static int king_vector[8] = {
 bitboard_t bitboard_between_excl(square_t sq1, square_t sq2)
 {
     const bitboard_t m1 = -1;
-    const bitboard_t a2a7 = C64(0x0001010101010100);
-    const bitboard_t b7h1 = C64(0x0002040810204080);
+    const bitboard_t a2a7 = U64(0x0001010101010100);
+    const bitboard_t b7h1 = U64(0x0002040810204080);
     bitboard_t btwn_bits, ray_bits;
     u32 rank_diff, file_diff, anti_diff, diag_diff;
 
@@ -109,7 +109,7 @@ void bitboard_init(void)
      *    in-between, sq2 excluded
      */
     for (square_t sq1 = A1; sq1 <= H8; ++sq1) {
-        bb_sq[sq1] = mask(sq1);
+        bb_sq[sq1] = BIT(sq1);
         for (square_t sq2 = A1; sq2 <= H8; ++sq2)
             bb_between_excl[sq1][sq2] = bitboard_between_excl(sq1, sq2);
     }
@@ -121,15 +121,15 @@ void bitboard_init(void)
         file_t f = sq_file(sq);
         rank_t r = sq_rank(sq);
         for (int vec = 0; vec < 4; ++vec) {
-            tmpbb[sq][vec] |= mask(sq_make(f, r));
+            tmpbb[sq][vec] |= BIT(sq_make(f, r));
             for (int dir = -1; dir <= 1; dir += 2) {
                 file_t df = dir * vecs[vec].df, f2 = f + df;
                 rank_t dr = dir * vecs[vec].dr, r2 = r + dr;
                 bitboard_t mask_between = 0;
                 while (sq_coord_ok(f2) && sq_coord_ok(r2)) {
                     square_t dest = sq_make(f2, r2);
-                    tmpbb[sq][vec] |= mask(dest);
-                    mask_between |= mask(dest);
+                    tmpbb[sq][vec] |= BIT(dest);
+                    mask_between |= BIT(dest);
                     bb_between[sq][dest] = mask_between;
                     f2 += df, r2 += dr;
                 }
@@ -160,10 +160,10 @@ void bitboard_init(void)
     /* 3) pawn, knight and king attacks
      */
     for (square_t sq = A1; sq <= H8; ++sq) {
-        if (sq >= A2)
-            bb_pawn_attacks[BLACK][sq] = pawn_attacks_bb(mask(sq), BLACK);
          if (sq <= H7)
-            bb_pawn_attacks[WHITE][sq] = pawn_attacks_bb(mask(sq), WHITE);
+             bb_pawn_attacks[WHITE][sq] = bb_pawns_attacks(BIT(sq), sq_up(WHITE));
+         if (sq >= A2)
+             bb_pawn_attacks[BLACK][sq] = bb_pawns_attacks(BIT(sq), sq_up(BLACK));
 
         for (int vec = 0; vec < 8; ++vec) {
             int dst = sq + knight_vector[vec];
@@ -281,7 +281,7 @@ char *bb_rank_sprint(char *str, const uchar bb8)
 {
     file_t f;
     for (f = FILE_A; f <= FILE_H; ++f) {
-        *(str + f) = bb8 & mask(f) ? '1': '.';
+        *(str + f) = bb8 & BIT(f) ? '1': '.';
     }
     *(str + f) = 0;
     //printf(" 0 1 2 3 4 5 6 7\n");

src/bitboard.h

@@ -234,12 +234,25 @@ static __always_inline bitboard_t bb_shift(bitboard_t bb, int shift)
    return shift >= 0 ? bb << shift : bb >> -shift;
 }
 
+/**
+ * bb_pawns_attacks() - shift up pawns on both diagonals (attacks)
+ * @bb:      pawns bitboard
+ * @push:    shift value for pawn up
+ *
+ * Get the possible attacks for all @bb pawns.
+ *
+ * @return: squares attacked by @bbpawns
+ */
+static __always_inline bitboard_t bb_pawns_attacks(const bitboard_t bb, int push)
+{
+    return bb_shift(bb & ~FILE_Abb, push - 1) | bb_shift(bb & ~FILE_Hbb, push + 1);
+}
 
 #define bb_rank(r)        ((u64) RANK_1bb << ((r) * 8))
 #define bb_file(f)        ((u64) FILE_Abb << (f))
 
 #define bb_rel_rank(r, c) bb_rank(sq_rel_rank(r, c))
-#define bb_rel_file(f, c) bb_file(sq_rel_rank(f, c))
+#define bb_rel_file(f, c) bb_file(sq_rel_rank(f, c)) /* likely useless */
 
 /**
  * bb_sq_aligned() - check if two squares are aligned (same file or rank).
@@ -260,7 +273,7 @@ static __always_inline bool bb_sq_aligned(square_t sq1, square_t sq2)
  */
 static __always_inline bool bb_sq_aligned3(square_t sq1, square_t sq2, square_t sq3)
 {
-    return bb_line[sq1][sq2] & mask(sq3);
+    return bb_line[sq1][sq2] & BIT(sq3);
 }
 
 /**
@@ -273,58 +286,9 @@ static __always_inline bool bb_sq_aligned3(square_t sq1, square_t sq2, square_t
  */
 static __always_inline bitboard_t bb_sq_between(square_t sq, square_t sq1, square_t sq2)
 {
-    return bb_between_excl[sq1][sq2] & mask(sq);
+    return bb_between_excl[sq1][sq2] & BIT(sq);
 }
 
-/* TODO: when OK, replace with macros */
-static __always_inline bitboard_t shift_n(const bitboard_t bb)
-{
-    return bb << NORTH;
-}
-static __always_inline bitboard_t shift_ne(const bitboard_t bb)
-{
-    return (bb & ~FILE_Hbb) << NORTH_EAST;
-}
-static __always_inline bitboard_t shift_e(const bitboard_t bb)
-{
-    return (bb & ~FILE_Hbb) << EAST;
-}
-static __always_inline bitboard_t shift_se(const bitboard_t bb)
-{
-    return (bb & ~FILE_Hbb) >> -SOUTH_EAST;
-}
-static __always_inline bitboard_t shift_s(const bitboard_t bb)
-{
-    return bb >> -SOUTH;
-}
-static __always_inline bitboard_t shift_sw(const bitboard_t bb)
-{
-    return (bb & ~FILE_Abb) >> -SOUTH_WEST;
-}
-static __always_inline bitboard_t shift_w(const bitboard_t bb)
-{
-    return (bb & ~FILE_Abb) >> -WEST;
-}
-static __always_inline bitboard_t shift_nw(const bitboard_t bb)
-{
-    return (bb & ~FILE_Abb) << NORTH_WEST;
-}
-
-/* pawn moves/attacks (for bitboards) */
-#define pawn_shift_up(bb, c)      ((c) == WHITE ? shift_n(bb): shift_s(bb))
-#define pawn_shift_upleft(bb, c)  ((c) == WHITE ? shift_nw(bb): shift_se(bb))
-#define pawn_shift_upright(bb, c) ((c) == WHITE ? shift_ne(bb): shift_sw(bb))
-
-#define pawn_attacks_bb(bb, c)    (pawn_shift_upleft(bb, c) |                   \
-                                   pawn_shift_upright(bb, c))
-
-/* pawn move (for single pawn) - NO SQUARE CONTROL HERE !
- * Need to make functions with control instead.
- */
-#define pawn_push_up(sq, c)       ((sq) + ((c) == WHITE ? NORTH:      SOUTH))
-//#define pawn_push_upleft(sq, c)   ((sq) + ((c) == WHITE ? NORTH_WEST: SOUTH_EAST))
-//#define pawn_push_upright(sq, c)  ((sq) + ((c) == WHITE ? NORTH_EAST: SOUTH_WEST))
-
 bitboard_t bitboard_between_excl(square_t sq1, square_t sq2);
 void bitboard_init(void);
 

src/board.c

@@ -14,7 +14,8 @@
 #include <stdio.h>
 #include <ctype.h>
 
-#include "brlib.h"
+#include <brlib.h>
+
 #include "board.h"
 #include "bitboard.h"
 
@@ -93,7 +94,7 @@ void board_print_mask(const piece_t *board, const bitboard_t mask)
         for (int file = 0; file < 8; ++file) {
             square_t sq = sq_make(file, rank);
             piece_t pc = board[sq];
-            bitboard_t set = mask(sq) & mask;
+            bitboard_t set = BIT(sq) & mask;
             printf("%s", set? REVERSE : " ");
 #           ifdef DIAGRAM_SYM
             printf("%s", pc? piece_to_sym(pc): " ");

src/chessdefs.h

@@ -16,11 +16,12 @@
 
 #include "brlib.h"                                /* brlib types */
 
-#define ONE                1ull
-#define C64(const_u64)     const_u64##ULL
-#define mask(i)            ( (u64) (ONE << (i)) )
+#define ONE                1ul
+#define U64(const_u64)     const_u64##UL
+#define BIT(i)             ( (u64) (ONE << (i)) )
 
 #define BOARDSIZE          (8*8)
+#define GAMESIZE           1024                   /* max game size (512 moves) */
 
 /**
  * sq_rel - get relative square
@@ -50,17 +51,19 @@
 /* castle_t bits structure
  */
 typedef enum {
-    CASTLE_WK = (1 << 0),                         /* 0x01 00000001 */
-    CASTLE_WQ = (1 << 1),                         /* 0x02 00000010 */
-    CASTLE_BK = (1 << 2),                         /* 0x04 00000100 */
-    CASTLE_BQ = (1 << 3),                         /* 0x08 00001000 */
+    CASTLE_NONE = 0,
+    CASTLE_WK   = (1 << 0),                       /* 0001 */
+    CASTLE_WQ   = (1 << 1),                       /* 0010 */
+    CASTLE_BK   = (1 << 2),                       /* 0100 */
+    CASTLE_BQ   = (1 << 3),                       /* 1000 */
 
-    CASTLE_W  = (CASTLE_WK | CASTLE_WQ),          /* 00000011 W castle mask */
-    CASTLE_B  = (CASTLE_BK | CASTLE_BQ),          /* 00001100 B castle mask */
+    CASTLE_W    = (CASTLE_WK | CASTLE_WQ),        /* 0011 =  3 = W castle mask */
+    CASTLE_B    = (CASTLE_BK | CASTLE_BQ),        /* 1100 = 12 = B castle mask */
+    CASTLE_ALL  = (CASTLE_W | CASTLE_B),          /* 1111 = 15 */
 
     CASTLE_K  = (1 << 0),                         /* generic K/Q, bits 0 and 1 */
     CASTLE_Q  = (1 << 1),
-    CASTLE_KQ = (CASTLE_K |CASTLE_Q)
+    CASTLE_KQ = (CASTLE_K |CASTLE_Q),
 } castle_rights_t;
 
 /* determine is oo or ooo is possible with castle flags f and color c
@@ -137,8 +140,10 @@ typedef enum {
 
 /* define diff for relative squares */
 #define sq_up(c)          ((c) == WHITE ? NORTH: SOUTH)
-#define sq_upleft(c)      ((c) == WHITE ? NORTH_WEST: SOUTH_EAST)
-#define sq_upright(c)     ((c) == WHITE ? NORTH_EAST: SOUTH_WEST)
+/* Attention here: We mix "up" (color dependent) and W/E, color independant.
+ */
+#define sq_upwest(up)     ((up) - 1)
+#define sq_upeast(up)     ((up) + 1)
 
 #include <time.h>
 
@@ -171,4 +176,11 @@ 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.h

@@ -1,6 +1,6 @@
 /* eval.h - static position evaluation.
  *
- * Copyright (C) 2021 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.
  *

src/fen.c

@@ -61,46 +61,50 @@ static const char *castle_str = "KQkq";
 #define SKIP_BLANK(p) for(;isspace(*(p)); (p)++)
 
 /**
- * fen_check(pos_t *pos) - test (and try to fix) fen-generated position.
- * @pos: position
+ * fen_ok() - test (and try to fix) fen-generated position.
+ * @pos:    &position
+ * @fixit:  action flag
  *
- * Test and fix the following:
+ * Test and possibly fix the following:
  * - inconsistent castle flags (if K & R are not in correct position)
- * - inconsistent en-passant square (turn, bad pawn position)
+ * - inconsistent en-passant square (turn, bad pawns positions)
  *
- * pos_check() is also called, leading to fatal errors if something is wrong.
+ * if @fixit is true, any error above will be fixed, and pos_ok() will
+ is also called, leading to fatal errors if something is wrong.
  *
  * @return: 0 if OK, 1 if OK after fix, -1 if fatal issue.
  */
-static int fen_check(pos_t *pos)
+int fen_ok(pos_t *pos, bool fixit)
 {
     char *colstr[2] = { "white", "black"};
     int warning = 0;
+    color_t us = pos->turn, them = OPPONENT(us);
+    int up = sq_up(us);                           /* pawn up */
+    square_t ep = pos->en_passant;
 
     /* en passant, depends on who plays next */
-    if (pos->en_passant != SQUARE_NONE) {
-        rank_t eprank = sq_rank(pos->en_passant);
-        file_t epfile = sq_file(pos->en_passant);
-        rank_t rank5 = sq_rel_rank(RANK_5, pos->turn);
-        rank_t rank6 = sq_rel_rank(RANK_6, pos->turn);
-        rank_t rank7 = sq_rel_rank(RANK_7, pos->turn);
-        piece_t pawn = pos->turn == WHITE? B_PAWN: W_PAWN;
-        if (warn(eprank != rank6 ||
-                 pos->board[sq_make(epfile, rank5)] != pawn ||
-                 pos->board[sq_make(epfile, rank6)] != EMPTY ||
-                 pos->board[sq_make(epfile, rank7)] != EMPTY,
-                 "fen warn: wrong en-passant settings. (fixed)\n")) {
-#           ifdef DEBUG_FEN
-            printf("ep5=%o ep6=%o ep7=%o\n", sq_make(epfile, rank5),
-                   sq_make(epfile, rank6), sq_make(epfile, rank7));
-#           endif
+    if (ep != SQUARE_NONE) {
+        rank_t eprank = sq_rank(ep);
+        rank_t rank6 = sq_rel_rank(RANK_6, us);
+        piece_t pawn = MAKE_PIECE(PAWN, them);
+        bitboard_t att = bb_pawn_attacks[them][ep] & pos->bb[us][PAWN];
+
+        if (eprank != rank6 ||
+            pos->board[ep - up] != pawn ||
+            pos->board[ep] != EMPTY ||
+            pos->board[ep + up] != EMPTY ||
+            att == 0ull) {
+
             warning++;
+            if (fixit) {
+                warn(true, "pos warn: wrong en-passant settings (fixed).\n");
                 pos->en_passant = SQUARE_NONE;
             }
         }
+    }
 
     for (int color = WHITE; color <= BLACK; ++color) {
-        rank_t rank1 = color == WHITE? RANK_1: RANK_8;
+        rank_t rank1 = sq_rel_rank(RANK_1, color);
 
         /* castling */
         /* where K and R should be for valid castle flag */
@@ -109,28 +113,28 @@ static int fen_check(pos_t *pos)
         bitboard_t r_q  = bb_sq[sq_make(FILE_A, rank1)];
 
        /* where they are */
-        bitboard_t kings = pos->bb[color][KING];
-        bitboard_t rooks = pos->bb[color][ROOK];
+        bitboard_t kingbb = pos->bb[color][KING];
+        bitboard_t rookbb = pos->bb[color][ROOK];
         castle_rights_t castle_k = color == WHITE? CASTLE_WK: CASTLE_BK;
         castle_rights_t castle_q = color == WHITE? CASTLE_WQ: CASTLE_BQ;
-        if (pos->castle & castle_k) {
-            if (warn(!(k & kings && r_k & rooks),
-                     "fen warn: wrong %s short castling K or R position (fixed)\n",
-                     colstr[color])) {
+        if (pos->castle & castle_k && !(k & kingbb && r_k & rookbb)) {
             warning++;
+            if (fixit) {
+                warn(true, "fen warn: wrong %s short castling (fixed)\n",
+                     colstr[color]);
                 pos->castle &= ~castle_k;
             }
         }
-        if (pos->castle & castle_q) {
-            if (warn(!(k & kings && r_q & rooks),
-                     "fen warn: wrong %s long castling K or R position (fixed)\n",
-                     colstr[color])) {
+        if (pos->castle & castle_q && !(k & kingbb && r_q & rookbb)) {
             warning++;
+            if (fixit) {
+                warn(true, "fen warn: wrong %s long castling (fixed)\n",
+                     colstr[color]);
                 pos->castle &= ~castle_q;
             }
         }
     }
-    return pos_ok(pos, 0) ? warning: -1;
+    return warning;
 }
 
 /**
@@ -162,7 +166,7 @@ pos_t *fen2pos(pos_t *pos, const char *fen)
     char *p;
     short rank, file, tmp;
     piece_t piece;
-    int consumed, err_line = 0, err_pos, err_char;
+    int consumed, err_line = 0, err_pos = 0, err_char = 0;
     pos_t tmppos;
 
     pos_clear(&tmppos);
@@ -184,6 +188,8 @@ pos_t *fen2pos(pos_t *pos, const char *fen)
                   piece, PIECE(piece), COLOR(piece));
 #           endif
             pos_set_sq(&tmppos, sq_make(file, rank), piece);
+            if (PIECE(piece) == KING)
+                tmppos.king[COLOR(piece)] = sq_make(file, rank);
             file++;
         } else {                                  /* error */
             err_line = __LINE__, err_char = *cur, err_pos = cur - fen;
@@ -248,13 +254,15 @@ end:
              err_line, err_pos, err_char, err_char)) {
         return NULL;
     }
-    if (fen_check(&tmppos) < 0)
-        return NULL;
+
+    fen_ok(&tmppos, true);                        /* fix e.p & castling flags */
+    if (!pos_ok(&tmppos, false))
+        return NULL;                              /* invalid position: ignored */
+
+    tmppos.key = zobrist_calc(&tmppos);
     if (!pos)
-        pos = pos_dup(&tmppos);
-    //puts("prout 1");
-    //pos_print_raw(&tmppos, 1);
-    //puts("prout 2");
+        pos = pos_new();
+    pos_copy(&tmppos, pos);
 #   ifdef DEBUG_FEN
     pos_print_raw(&tmppos, 1);
 #   endif
@@ -324,7 +332,7 @@ char *pos2fen(const pos_t *pos, char *fen)
         fen[cur++] = '-';
     } else {
         for (int i = 0; i < 4; ++i)
-            if (pos->castle & mask(i))
+            if (pos->castle & BIT(i))
                 fen[cur++] = castle_str[i];
     }
     fen[cur++] = ' ';
@@ -334,8 +342,8 @@ char *pos2fen(const pos_t *pos, char *fen)
     if (pos->en_passant == SQUARE_NONE) {
         fen[cur++] = '-';
     } else {
-        fen[cur++] = FILE2C(sq_file(pos->en_passant));
-        fen[cur++] = RANK2C(sq_rank(pos->en_passant));
+        strcpy(fen+cur, sq_to_string(pos->en_passant));
+        cur += 2;
     }
     fen[cur++] = ' ';
 

src/fen.h

@@ -20,6 +20,7 @@
 
 extern const char *startfen;                      /* startup position */
 
+extern int fen_ok(pos_t *pos, bool fixit);
 extern pos_t *startpos(pos_t *pos);
 extern pos_t *fen2pos(pos_t *pos, const char *fen);
 extern char *pos2fen(const pos_t *pos, char *fen);

src/hash.c

@@ -0,0 +1,395 @@
+/* hash.c - hash 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 <string.h>
+#include <assert.h>
+
+#include <brlib.h>
+#include <bitops.h>
+
+#include "chessdefs.h"
+#include "util.h"
+#include "position.h"
+#include "piece.h"
+#include "hash.h"
+
+u64 zobrist_pieces[16][64];
+u64 zobrist_castling[4 * 4 + 1];
+u64 zobrist_turn;                                 /* for black, XOR each ply */
+u64 zobrist_ep[9];                                /* 0-7: ep file, 8: SQUARE_NONE */
+
+hasht_t hash_tt;                                  /* main transposition table */
+
+/**
+ * zobrist_init() - initialize zobrist tables.
+ *
+ * Initialize all zobrist random bitmasks. Must be called before any other
+ * zobrist function, and can be called once only (further calls will be ignored).
+ */
+void zobrist_init(void)
+{
+    static bool called = false;
+    if (!called) {
+        called = true;
+        for (color_t c = WHITE; c <= BLACK; ++c) {
+            for (piece_type_t p = PAWN; p <= KING; ++p)
+                for (square_t sq = A1; sq <= H8; ++sq)
+                    zobrist_pieces[MAKE_PIECE(p, c)][sq] = rand64();
+        }
+        for (castle_rights_t c = CASTLE_NONE; c <= CASTLE_ALL; ++c)
+            zobrist_castling[c] = rand64();
+        for (file_t f = FILE_A; f <= FILE_H; ++f)
+            zobrist_ep[f] = rand64();
+        zobrist_ep[8] = 0;                        /* see EP_ZOBRIST_IDX macro */
+        zobrist_turn = rand64();
+    }
+}
+
+/**
+ * zobrist_calc() - calculate a position zobrist hash.
+ * @pos: &position
+ *
+ * Normally, Zobrist keys are incrementally calculated when doing or
+ * undoing a move.
+ * This function should normally only be called:
+ * - When starting a new position
+ * - To verify incremental Zobrist calculation is correct
+ *
+ * @return: @pos Zobrist key
+ */
+hkey_t zobrist_calc(pos_t *pos)
+{
+    hkey_t key = 0;
+
+    if (pos->turn == BLACK)
+        key ^= zobrist_turn;
+
+    for (color_t c = WHITE; c <= BLACK; ++c) {
+        for (piece_type_t pt = PAWN; pt <= KING; ++pt) {
+            piece_t piece = MAKE_PIECE(pt, c);
+            bitboard_t bb = pos->bb[c][pt];
+            while (bb) {
+                square_t sq = bb_next(&bb);
+                key ^= zobrist_pieces[piece][sq];
+            }
+        }
+    }
+    key ^= zobrist_castling[pos->castle];
+    key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
+
+    return key;
+}
+
+/**
+ * zobrist_verify() - verify current position Zobrist key.
+ * @pos: &position
+ *
+ * Verify that position Zobrist key matches a full Zobrist calculation.
+ * This function cannot be called if ZOBRIST_VERIFY is not set.
+ *
+ * @return: True if Zobrist key is OK.
+ */
+#ifdef ZOBRIST_VERIFY
+
+#pragma push_macro("BUG_ON")                      /* force BUG_ON and WARN_ON */
+#pragma push_macro("WARN_ON")
+#undef BUG_ON
+#define BUG_ON
+#undef WARN_ON
+#define WARN_ON
+
+bool zobrist_verify(pos_t *pos)
+{
+    hkey_t diff, key = zobrist_calc(pos);
+
+    if (pos->key == key)
+        return true;
+
+    printf("key verify: cur=%#lx != %#lx\n", pos->key, key);
+
+    /* try to find-out the key in different zobrist tables */
+    diff = pos->key ^ key;
+
+    for (color_t c = WHITE; c <= BLACK; ++c) {
+        for (piece_type_t p = PAWN; p <= KING; ++p)
+            for (square_t sq = A1; sq <= H8; ++sq)
+                if (diff == zobrist_pieces[MAKE_PIECE(p, c)][sq]) {
+                    warn(true, "zobrist difference is piece:[%s][%s]\n",
+                         piece_to_fen(MAKE_PIECE(p, c)), sq_to_string(sq));
+                    goto end;
+                }
+    }
+    for (castle_rights_t c = CASTLE_NONE; c <= CASTLE_ALL; ++c) {
+        if (diff == zobrist_castling[c]) {
+            warn(true, "zobrist difference is castling:[%d]\n", c);
+            goto end;
+        }
+    }
+
+    for (file_t f = FILE_A; f <= FILE_H; ++f) {
+        if (diff == zobrist_ep[f]) {
+            warn(true, "zobrist difference is ep:[%d]\n", f);
+            goto end;
+        }
+    }
+    if (diff == zobrist_turn) {
+        warn(true, "zobrist difference is turn\n");
+        goto end;
+    }
+    warn(true, "zobrist diff %lx is unknown\n", diff);
+end:
+    bug_on(false);
+    /* not reached */
+    return true;
+}
+#pragma pop_macro("WARN_ON")
+#pragma pop_macro("BUG_ON")
+
+#endif
+
+/**
+ * tt_create() - create transposition table
+ * @sizemb: s32 size of hash table in Mb
+ *
+ * Create a hash table of max @sizemb (or HASH_SIZE_MBif @sizemb <= 0) Mb size.
+ * This function must be called at startup.
+ *
+ * The number of bucket_t entries fitting in @sizemb is calculated, and rounded
+ * (down) to a power of 2.
+ * This means the actual size could be lower than @sizemb (nearly halved in
+ * worst case).
+ *
+ * If transposition hashtable already exists and new size would not change,
+ * the old one is cleared.
+ * If transposition hashtable already exists and new size is different,
+ * the old one is destroyed first (old data is not preserved).
+ *
+ * TODO:
+ * - Rebuild old hashtable data ?
+ *
+ * @return: hash table size in Mb. If memory allocation fails, the function does
+ * not return.
+ */
+int tt_create(s32 sizemb)
+{
+    size_t bytes, target_nbuckets;
+    u32 nbits;
+
+    static_assert(sizeof(hentry_t) == 16, "fatal: hentry_t size != 16");
+
+    //printf("mb = %'7u ", sizemb);
+    /* adjust tt size */
+    if (sizemb <= 0)
+        sizemb = HASH_SIZE_DEFAULT;
+    sizemb = clamp(sizemb, HASH_SIZE_MIN, HASH_SIZE_MAX);
+    //printf("-> %'6d ", sizemb);
+
+    bytes = sizemb * 1024ull * 1024ull;           /* bytes wanted */
+    target_nbuckets = bytes / sizeof(bucket_t);   /* target buckets */
+
+    nbits = msb64(target_nbuckets);               /* adjust to power of 2 */
+
+    if (hash_tt.nbits != nbits) {
+        if (hash_tt.nbits)
+            tt_delete();
+
+        hash_tt.nbits    = nbits;
+
+        hash_tt.nbuckets = BIT(hash_tt.nbits);
+        hash_tt.nkeys    = hash_tt.nbuckets * ENTRIES_PER_BUCKET;
+
+        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.keys     = safe_malloc(hash_tt.bytes);
+
+        //printf("bits=%2d size=%'15lu/%'6d Mb/%'14lu buckets ",
+        //       hash_tt.nbits, hash_tt.bytes, hash_tt.mb, hash_tt.nbuckets);
+        //printf("mask=%9x\n", hash_tt.mask);
+    }
+    //else {
+    //    printf("unchanged (cleared)\n");
+    //}
+    /* attention - may fail ! */
+    tt_clear();
+
+    return hash_tt.nbits;
+}
+
+/**
+ * tt_clear() - clear transposition table
+ *
+ * Reset hashtable entries (if available) and statistic information.
+ */
+void tt_clear()
+{
+    if (hash_tt.keys)
+        memset(hash_tt.keys, 0, hash_tt.bytes);
+
+    hash_tt.used_keys = 0;
+    hash_tt.collisions = 0;
+    hash_tt.hits = 0;
+    hash_tt.misses = 0;
+}
+
+/**
+ * tt_delete() - delete transposition table
+ *
+ * free hashtable data.
+ */
+void tt_delete()
+{
+    if (hash_tt.keys)
+        safe_free(hash_tt.keys);
+    memset(&hash_tt, 0, sizeof(hash_tt));
+}
+
+/**
+ * tt_probe() - probe tt for an entry
+ *
+ *
+ */
+hentry_t *tt_probe(hkey_t key)
+{
+    bucket_t *bucket;
+    hentry_t *entry;
+    int i;
+
+    bug_on(!hash_tt.keys);
+    bucket = hash_tt.keys + (key & hash_tt.mask);
+
+    /* find key in buckets */
+    for (i = 0; i < ENTRIES_PER_BUCKET; ++i) {
+        entry = bucket->entry + i;
+        if (key == entry->key)
+            break;
+    }
+    if (i < ENTRIES_PER_BUCKET)
+        return entry;
+    return NULL;
+}
+
+/**
+ * tt_probe_perft() - probe tt for an entry (perft version)
+ * @key:   Zobrist (hkey_t) key
+ * @depth: depth from search root
+ *
+ * Search transposition for @key entry with @depth depth.
+ *
+ * @return: @hentry_t address is found, TT_MISS otherwise.
+ */
+hentry_t *tt_probe_perft(const hkey_t key, const u16 depth)
+{
+    bucket_t *bucket;
+    hentry_t *entry;
+    int i;
+
+    bug_on(!hash_tt.keys);
+    bucket = hash_tt.keys + (key & hash_tt.mask);
+
+    /* find key in buckets */
+    for (i = 0; i < ENTRIES_PER_BUCKET; ++i) {
+        entry = bucket->entry + i;
+        if (key == entry->key && HASH_PERFT_DEPTH(entry->data) == depth) {
+            hash_tt.hits++;
+            //printf("tt hit: key=%lx bucket=%lu entry=%d!\n",
+            //       key, bucket - hash_tt.keys, i);
+            return entry;
+        }
+    }
+    //printf("tt miss: key=%lx bucket=%lu\n",
+    //       key, bucket - hash_tt.keys);
+    hash_tt.misses++;
+    return TT_MISS;
+}
+
+/**
+ * tt_store_perft() - store a transposition table entry (perft version)
+ * @key:   Zobrist (hkey_t) key
+ * @depth: depth from search root
+ * @nodes: value to store
+ *
+ */
+hentry_t *tt_store_perft(const hkey_t key, const u16 depth, const u64 nodes)
+{
+    bucket_t *bucket;
+    hentry_t *entry;
+    int replace = -1, newkey = 0;
+    uint mindepth = 1024;
+    u64 data = HASH_PERFT(depth, nodes);
+
+    //printf("tt_store: key=%lx data=%lx depth=%d=%d nodes=%lu=%lu\n",
+    //       key, data, depth, HASH_PERFT_DEPTH(data), nodes, HASH_PERFT_VAL(data));
+    printf("tt_store: key=%lx depth=%d nodes=%lu ",
+           key, depth, nodes);
+    bug_on(!hash_tt.keys);
+    bucket = hash_tt.keys + (key & hash_tt.mask);
+
+    /* find key in buckets */
+    for (int i = 0; i < ENTRIES_PER_BUCKET; ++i) {
+        entry = bucket->entry + i;
+        if (key == entry->key && HASH_PERFT_DEPTH(entry->data)) {
+            printf("tt_store: sup key/depth, this should not happen!\n");
+            return NULL;
+        }
+        if (!entry->key) {
+            replace = i;
+            break;
+        }
+        /* we replace hash if we are higher in tree */
+        if (HASH_PERFT_DEPTH(entry->data) < mindepth) {
+            mindepth = HASH_PERFT_DEPTH(entry->data);
+            replace = i;
+        }
+        /*
+         * else {
+         *
+         *     if (key == entry->key && HASH_PERFT_DEPTH(entry->data) > mindepth) {
+         *         mindepth = HASH_PERFT_DEPTH(entry->data);
+         *         replace = i;
+         *     }
+         * }
+         */
+    }
+    if (replace >= 0) {
+        entry = bucket->entry + replace;
+        if (HASH_PERFT_VAL(entry->data)) {
+            printf("REPL entry=%lu[%d] key=%lx->%lx val=%lu->%lu\n",
+                   bucket - hash_tt.keys, replace,
+                   entry->key, key,
+                   HASH_PERFT_VAL(entry->data), nodes);
+        } else {
+            printf("NEW entry=%lu[%d] key=%lx val=%lu\n",
+                   bucket - hash_tt.keys, replace,
+                   entry->key, nodes);
+        }
+        entry->key = key;
+        entry->data = data;
+        return entry;
+    } else {
+        printf("TT full, skip\n");
+    }
+    return NULL;
+}
+
+void tt_stats()
+{
+    printf("TT: sz=%u bits=%u bcks=%'lu entries=%'lu mask=%10x"
+           "used=%lu hits/miss=%'lu/%'lu\n",
+           hash_tt.mb, hash_tt.nbits, hash_tt.nbuckets, hash_tt.nkeys, hash_tt.mask,
+           hash_tt.used_keys, hash_tt.hits, hash_tt.misses);
+    //printf("\tused=%lu hits/miss=%lu/%lu\n",
+    //       hash_tt.used_keys, hash_tt.hits, hash_tt.misses);
+}

src/hash.h

@@ -0,0 +1,135 @@
+/* hash.h - hash 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>
+ *
+ */
+
+#ifndef HASH_H
+#define HASH_H
+
+#include <bug.h>
+
+#include "chessdefs.h"
+
+#define ENTRIES_PER_BUCKET   4                    /* buckets per hash table entry */
+
+#define HASH_SIZE_DEFAULT   32                    /* default: 32Mb */
+#define HASH_SIZE_MIN        4
+#define HASH_SIZE_MAX    32768                    /* 32Gb */
+
+#define TT_MISS           NULL
+
+typedef u64 hkey_t;                               /* cannot use typedef for key_t */
+
+/**
+ * hentry_t: hashtable bucket.
+ *
+ * Size should be exactly 16 bytes. If impossible to fit necessary data in
+ * 16 bytes in future, it should be updated to be exactly 32 bytes.
+ */
+typedef struct {
+    hkey_t key;                                   /* zobrist */
+    union {
+        u64 data;
+        struct {
+            u16 depth;                            /* ply in search */
+            s16 eval;
+            u16 move;
+            u8 flags;                             /* maybe for locking, etc... */
+            u8 filler;
+        };
+    };
+} hentry_t;
+
+/* hentry perft data:
+ * 0-47:  perft value
+ * 48-63: depth
+ */
+#define HASH_PERFT_MASK        U64(0xffffffffffff)
+#define HASH_PERFT(depth, val) ((((u64) depth) << 48) | ((val) & HASH_PERFT_MASK))
+#define HASH_PERFT_VAL(data)   ((data) & HASH_PERFT_MASK)
+#define HASH_PERFT_DEPTH(data) ((u16)((data) >> 48))
+
+
+typedef struct {
+    hentry_t entry[ENTRIES_PER_BUCKET];
+} bucket_t;
+
+typedef struct {
+    bucket_t *keys;                               /* &hashtable entries */
+
+    /* memory size in bytes/mb */
+    size_t bytes;
+    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 */
+
+    /* stats - unsure about usage */
+    //size_t used_buckets;
+    size_t used_keys;
+    u64 collisions;
+    u64 hits;
+    u64 misses;
+} hasht_t;
+
+/* hack:
+ *  ep zobrist key index is 0-7 for each en-passant file, 8 for SQUARE_NONE.
+ * To transform :
+ *   - ep == 64 (SQUARE_NONE) to id = 8
+ *   - ep == 0~63 to idx = sq_file(ep), i.e. (ep & 7)
+ * we use the formula:
+ * idx = ( ( ep & SQUARE_NONE ) >> 3 ) | sq_file(ep);
+ */
+#define EP_ZOBRIST_IDX(ep) ( ( (ep) >> 3 ) | sq_file(ep) )
+
+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 hasht_t hash_tt;                           /* main transposition table */
+
+void zobrist_init(void);
+hkey_t zobrist_calc(pos_t *pos);
+
+#ifdef ZOBRIST_VERIFY
+bool zobrist_verify(pos_t *pos);
+#else
+#define zobrist_verify(p) true
+#endif
+
+/**
+ * tt_prefetch() - prefetch hash table entry
+ * @hash: u64 key
+ *
+ * Prefetch memory for @key.
+ */
+static inline void tt_prefetch(hkey_t key)
+{
+    bug_on(!hash_tt.keys);
+    __builtin_prefetch(hash_tt.keys + (key & hash_tt.mask));
+}
+
+int tt_create(int Mb);
+void tt_clear(void);
+void tt_delete(void);
+
+hentry_t *tt_probe(hkey_t key);
+hentry_t *tt_probe_perft(const hkey_t key, const u16 depth);
+hentry_t *tt_store_perft(const hkey_t key, const u16 depth, const u64 nodes);
+void tt_stats(void);
+
+#endif  /* HASH_H */

src/hyperbola-quintessence.c

@@ -129,8 +129,8 @@ bitboard_t hyperbola_moves(const bitboard_t pieces, const square_t sq,
     bitboard_t r = bswap64(o);
     square_t  r_sq = FLIP_V(sq);
 
-    return (         (o - 2 * mask(sq)   )
-            ^ bswap64(r - 2 * mask(r_sq)))
+    return (         (o - 2 * BIT(sq)   )
+            ^ bswap64(r - 2 * BIT(r_sq)))
         & mask;
 }
 

src/init.c

@@ -0,0 +1,42 @@
+/* init.c - initialize all.
+ *
+ * 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 <locale.h>
+
+#include "chessdefs.h"
+
+#include "bitboard.h"
+#include "hyperbola-quintessence.h"
+
+#include "hash.h"
+
+void init_all(void)
+{
+    /* for printf() numeric thousands separator */
+    setlocale(LC_NUMERIC, "");
+    /* line-buffered stdout */
+    setlinebuf(stdout);
+
+    /* pseudo random generator seed */
+    rand_init(RAND_SEED_DEFAULT);
+
+    /* bitboards & hq */
+    bitboard_init();
+    hyperbola_init();
+
+    /* zobrist tables & default tt hashtable */
+    zobrist_init();
+    tt_create(HASH_SIZE_DEFAULT);
+
+}

src/misc.c

@@ -12,6 +12,9 @@
  */
 
 #include <time.h>
+#include <stdlib.h>
+
+#include <bug.h>
 
 #include "chessdefs.h"
 
@@ -110,3 +113,40 @@ double clock_elapsed_sec(mclock_t *clock)
 {
     return (double) clock_elapsed_μs(clock) / (double) MICRO_IN_SEC;
 }
+
+static u64 rand_seed = 1ull;
+
+/**
+ * rand_init() - initialize random generator seed.
+ * @seed: u64, the random generator seed.
+ *
+ * No change is made is performed if If @seed is zero. By default, @seed is
+ * 1.
+ * This seed is used by rand64().
+ */
+void rand_init(u64 seed)
+{
+    if (seed)
+        rand_seed = seed;
+}
+
+/**
+ * rand64() - get a random number, xorshift method.
+ *
+ * Source:
+ *   https://en.wikipedia.org/wiki/Xorshift#xorshift*
+ * We do not want true random numbers, like those offered by getrandom(2), as we
+ * need to be able to get predictable results.
+ * Note: For predictable results in MT, we should use separate seeds.
+ *
+ * @return: a 64 bits random number.
+ */
+u64 rand64(void)
+{
+    bug_on(rand_seed == 0ull);
+
+    rand_seed ^= rand_seed >> 12;
+    rand_seed ^= rand_seed << 25;
+    rand_seed ^= rand_seed >> 27;
+    return rand_seed * 0x2545f4914f6cdd1dull;
+}

src/move-do.c

@@ -23,6 +23,7 @@
 #include "move.h"
 #include "position.h"
 #include "move-do.h"
+#include "hash.h"
 
 /**
  * move_do() - do move.
@@ -39,24 +40,30 @@
  *   - castling
  *   - en-passant
  * - captured piece (excl. en-passant)
+ * - tt hash values are updated for:
+ *   - side-to-move
+ *   - en-passant
+ *   - castling rights.
  *
- * @return: pos.
+ * @return: updated pos.
  */
-pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
+pos_t *move_do(pos_t *pos, const move_t move, state_t *state)
 {
-//#   ifdef DEBUG_MOVE_DO
-//    move_print(move, M_PR_NL | M_PR_LONG);
-//#   endif
-    //*state = pos->state;                          /* save irreversible changes */
-
     color_t us = pos->turn, them = OPPONENT(us);
     square_t from = move_from(move), to = move_to(move);
     piece_t piece = pos->board[from];
     piece_t captured = pos->board[to];
     piece_type_t ptype = PIECE(piece);
-    color_t pcolor = COLOR(piece);
     piece_t new_piece = piece;
     int up = sq_up(us);
+    hkey_t key = pos->key;
+
+    *state = pos->state;                          /* save irreversible changes */
+
+    /* update key: switch turn, reset castling and ep */
+    key ^= zobrist_turn;
+    key ^= zobrist_castling[pos->castle];
+    key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
 
     ++pos->clock_50;
     ++pos->plycount;
@@ -64,7 +71,7 @@ pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
     pos->turn = them;
     pos->captured = captured;
 
-    bug_on(pcolor != us);
+    bug_on(COLOR(piece) != us);
 
     if (is_promotion(move)) {
         bug_on(sq_rank(to) != sq_rel_rank(RANK_8, us));
@@ -75,6 +82,7 @@ pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
         pos->clock_50 = 0;
         //pos->captured = pos->board[to];           /* save capture info */
         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;
@@ -85,20 +93,29 @@ pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
             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->clock_50 = 0;
-        if (is_dpush(move))                       /* if pawn double push, set e.p. */
-            pos->en_passant = from + up;
-        else if (is_enpassant(move)) {            /* clear grabbed pawn */
+        if (from + up + up == to) {               /* if pawn double push, set e.p. */
+            square_t ep = from + up;;
+            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 */
             square_t grabbed = to - up;
+            piece_t pc = pos->board[grabbed];
+            key ^= zobrist_pieces[pc][grabbed];
             pos_clr_sq(pos, grabbed);
         }
     }
 
-    pos_clr_sq(pos, from);                        /* always clear "from" and set "to" */
+    key ^= zobrist_pieces[piece][from] ^ zobrist_pieces[new_piece][to];
+    pos_clr_sq(pos, from);                        /* clear "from" and set "to" */
     pos_set_sq(pos, to, new_piece);
 
     if (ptype == KING)
@@ -120,7 +137,7 @@ pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
         else if (from == rel_h1)
             pos->castle = clr_oo(pos->castle, us);
     }
-    if (can_castle(pos->castle, them)) {          /* do we save time with this test ? */
+    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)
@@ -129,6 +146,13 @@ pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
             pos->castle = clr_oo(pos->castle, them);
     }
 
+    /* update castling rights key */
+    key ^= zobrist_castling[pos->castle];
+
+    pos->key = key;
+
+    zobrist_verify(pos);
+
     return pos;
 }
 
@@ -149,12 +173,156 @@ pos_t *move_do(pos_t *pos, const move_t move) //, state_t *state)
  *
  * @return: pos.
  */
-pos_t *move_undo(pos_t *pos, const move_t move)//, const state_t *state)
+pos_t *move_undo(pos_t *pos, const move_t move, const state_t *state)
+{
+    color_t them = pos->turn, us = OPPONENT(them);
+    square_t from = move_from(move), to = move_to(move);
+    piece_t piece = pos->board[to];
+    int up = sq_up(them);
+
+    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" */
+
+    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 */
+        square_t rookfrom, rookto;
+        if (is_castle_K(move)) {
+            rookfrom = sq_rel(F1, us);
+            rookto = sq_rel(H1, us);
+        } else {
+            rookfrom = sq_rel(D1, us);
+            rookto = sq_rel(A1, us);
+        }
+        pos_set_sq(pos, rookto, pos->board[rookfrom]);
+        pos_clr_sq(pos, rookfrom);
+    } else if (is_enpassant(move)) {              /* restore grabbed pawn */
+        square_t grabbed = to + up;
+        pos_set_sq(pos, grabbed, MAKE_PIECE(PAWN, them));
+    }
+
+    pos->state = *state;                          /* restore irreversible changes */
+    pos->turn = us;
+    return pos;
+}
+
+/**
+ * move_{do,undo}_alt - alternative move_do/move_undo (to experiment)
+ */
+pos_t *move_do_alt(pos_t *pos, const move_t move) //, state_t *state)
+{
+    color_t us = pos->turn, them = OPPONENT(us);
+    square_t from = move_from(move), to = move_to(move);
+    piece_t piece = pos->board[from];
+    piece_t captured = pos->board[to];
+    piece_type_t ptype = PIECE(piece);
+    piece_t new_piece = piece;
+    int up = sq_up(us);
+    hkey_t key = pos->key;
+
+    /* update key: switch turn, reset castling and ep */
+    key ^= zobrist_turn;
+    key ^= zobrist_castling[pos->castle];
+    key ^= zobrist_ep[EP_ZOBRIST_IDX(pos->en_passant)];
+
+    ++pos->clock_50;
+    ++pos->plycount;
+    pos->en_passant = SQUARE_NONE;
+    pos->turn = them;
+    pos->captured = captured;
+
+    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) {
+        pos->clock_50 = 0;
+        //pos->captured = pos->board[to];           /* save capture info */
+        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 (is_castle_K(move)) {
+            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->clock_50 = 0;
+        if (from + up + up == to) {               /* if pawn double push, set e.p. */
+            square_t ep = from + up;;
+            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 */
+            square_t grabbed = to - up;
+            key ^= zobrist_pieces[pos->board[grabbed]][grabbed];
+            pos_clr_sq(pos, grabbed);
+        }
+    }
+
+    key ^= zobrist_pieces[piece][from] ^ zobrist_pieces[new_piece][to];
+    pos_clr_sq(pos, from);                        /* clear "from" and set "to" */
+    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 */
+    key ^= zobrist_castling[pos->castle];
+
+    pos->key = key;
+
+    zobrist_verify(pos);
+
+    return pos;
+}
+
+pos_t *move_undo_alt(pos_t *pos, const move_t move)
 {
-//#   ifdef DEBUG_MOVE
-    //log(1, "new move: ");
-    //move_print(0, move, M_PR_NL | M_PR_LONG);
-//#   endif
     color_t them = pos->turn, us = OPPONENT(them);
     square_t from = move_from(move), to = move_to(move);
     piece_t piece = pos->board[to];

src/move-do.h

@@ -16,7 +16,10 @@
 
 #include "position.h"
 
-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);
+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);
+
+pos_t *move_do_alt(pos_t *pos, const move_t move);//, state_t *state);
+pos_t *move_undo_alt(pos_t *pos, const move_t move);//, const state_t *state);
 
 #endif  /* MOVE_DO_H */

src/move-gen.c

@@ -41,7 +41,7 @@ bool pseudo_is_legal(const pos_t *pos, const move_t move)
     square_t king = pos->king[us];
     bitboard_t kingbb = pos->bb[us][KING];
     bitboard_t occ = pos_occ(pos);
-    u64 pinned = mask(from) & pos->blockers;
+    u64 pinned = BIT(from) & pos->blockers;
     u64 checkers = pos->checkers;
 
     /* (1) - Castling & King
@@ -53,10 +53,10 @@ bool pseudo_is_legal(const pos_t *pos, const move_t move)
     if (unlikely(from == king)) {
         if (unlikely(is_castle(move))) {
             square_t dir = to > from? 1: -1;
-            if (sq_attackers(pos, occ, from + dir, them))
+            if (sq_is_attacked(pos, occ, from + dir, them))
                 return false;
         }
-        return !sq_attackers(pos, occ ^ kingbb, to, them);
+        return !sq_is_attacked(pos, occ ^ kingbb, to, them);
     }
 
     /* (2) - King is in check
@@ -86,8 +86,8 @@ bool pseudo_is_legal(const pos_t *pos, const move_t move)
     /* (3) - pinned pieces
      * We verify here that pinned piece P stays on line King-P.
      */
-    if (mask(from) & pos->blockers) {
-        return bb_line[from][king] & mask(to);    /* is to on pinner line ? */
+    if (BIT(from) & pos->blockers) {
+        return bb_line[from][king] & BIT(to);    /* is to on pinner line ? */
     }
 
     /* (4) - En-passant
@@ -95,20 +95,17 @@ bool pseudo_is_legal(const pos_t *pos, const move_t move)
      * One case not handled anywhere else: when the two "disappearing" pawns
      * would discover a R/Q horizontal check.
      */
-    if (is_enpassant(move)) {
-        bitboard_t rank5 = us == WHITE? RANK_5bb: RANK_4bb;
+    if (unlikely(is_enpassant(move))) {
+        bitboard_t rank5 = bb_rel_rank(RANK_5, us);
 
-        if ((pos->bb[us][KING] & rank5)) {
-            bitboard_t exclude = mask(pos->en_passant - sq_up(us)) | mask(from);
+        if (unlikely((pos->bb[us][KING] & rank5))) {
+            bitboard_t exclude = BIT(pos->en_passant - sq_up(us)) | BIT(from);
             bitboard_t rooks = (pos->bb[them][ROOK] | pos->bb[them][QUEEN]) & rank5;
 
-            while (rooks) {
-                square_t rook = bb_next(&rooks);
-                if (hyperbola_rank_moves(occ ^ exclude, rook) & kingbb)
+            if (hyperbola_rank_moves(occ ^ exclude, king) & rooks)
                 return false;
         }
     }
-    }
     return true;
 }
 
@@ -138,24 +135,52 @@ move_t pos_next_legal(const pos_t *pos, movelist_t *movelist, int *start)
 }
 
 /**
- * pos_all_legal() - get the list of legal moves from pseudo-legal.
+ * pos_legal_dup() - get legal moves from pseudo-legal ones in new list.
  * @pos:  position
- * @movelist: &pseudo-legal movelist_t
- * @dest: &destination movelist_t
+ * @pseudo: &movelist_t pseudo-legal moves list
+ * @legal: &movelist_t legal moves
  *
  * The pseudo-legal moves must be already calculated before calling this function.
- * No check is done on @dest limits.
+ * No check is done on @legal limits.
+ * This function is similar to pos_legal(), but creates a new list for legal moves.
+ * It should only be used for debug purpose, when we want to keep a copy of
+ * pseudo-legal moves.
  *
- * @Return: @dest
+ * @return: @legal
  */
-movelist_t *pos_all_legal(const pos_t *pos, movelist_t *movelist, movelist_t *dest)
+movelist_t *pos_legal_dup(const pos_t *pos, movelist_t *pseudo, movelist_t *legal)
 {
-    int tmp = dest->nmoves = 0;
+    int tmp = legal->nmoves = 0;
     move_t move;
 
-    while ((move = pos_next_legal(pos, movelist, &tmp)) != MOVE_NONE)
-        dest->move[dest->nmoves++] = move;
-    return dest;
+    while ((move = pos_next_legal(pos, pseudo, &tmp)) != MOVE_NONE)
+        legal->move[legal->nmoves++] = move;
+    return legal;
+}
+
+/**
+ * pos_legal() - get legal moves from pseudo-legal ones in new list.
+ * @pos:  position
+ * @list: &movelist_t pseudo-legal moves list
+ *
+ * The pseudo-legal moves must be already calculated before calling this function.
+ * @list is replaced by legal moves.
+ *
+ * @return: @list
+ */
+movelist_t *pos_legal(const pos_t *pos, movelist_t *list)
+{
+    move_t *cur = list->move, *last = list->move + list->nmoves;
+
+    while (cur < last) {
+        if (pseudo_is_legal(pos, *cur))
+            cur++;
+        else {
+            *cur = *--last;
+        }
+    }
+    list->nmoves = last - list->move;
+    return list;
 }
 
 /**
@@ -230,16 +255,40 @@ static inline __unused move_t *gen_pseudo_king(move_t *moves, square_t from,
  */
 
 /**
- * move_make_promotions() - generate all promotions for given pawn and dest.
+ * moves_gen_flags() - generate all moves from square to bitboard (with flags).
+ * @moves: &move_t array where to store moves
+ * @from: square_t piece position
+ * @to_bb: destination bitboard
+ * @flags: flags to apply
+ *
+ * Generate (at address @moves) moves from square @from to each square in @to_bb,
+ * with flags @flags.
+ *
+ * @Return: New @moves.
+ */
+static inline __unused move_t *moves_gen_flags(move_t *moves, square_t from, bitboard_t to_bb,
+    __unused move_flags_t flags)
+{
+    square_t to;
+    while(to_bb) {
+        to = bb_next(&to_bb);
+        *moves++ = move_make_flags(from, to, flags);
+    }
+    return moves;
+}
+
+/**
+ * move_gen_promotions() - generate all promotions for given pawn and dest.
  * @moves: &move_t array where to store moves
  * @from: pawn position
  * @to: promotion square
  *
- * Generate all (Q/R/B/N) promotion moves on @to for pawn @from.
+ * Generate  (at address @moves) all promotion (Q/R/B/N) moves on @to for
+ * pawn @from.
  *
- * @Return: New @moves (incremented by 4).
+ * @Return: New @moves.
  */
-static inline move_t *move_make_promotions(move_t *moves, square_t from, square_t to)
+static inline move_t *move_gen_promotions(move_t *moves, square_t from, square_t to)
 {
     for (piece_type_t pt = QUEEN; pt >= KNIGHT; --pt)
         *moves++ = move_make_promote(from, to, pt);
@@ -247,7 +296,28 @@ static inline move_t *move_make_promotions(move_t *moves, square_t from, square_
 }
 
 /**
- * pos_gen_pseudomoves() - generate position pseudo-legal moves
+ * moves_gen() - generate all moves from square to bitboard.
+ * @moves: &move_t array where to store moves
+ * @from: square_t piece position
+ * @to_bb: destination bitboard
+ *
+ * Generate (at address @moves) moves from square @from to each square in @to_bb.
+ *
+ * @Return: New @moves.
+ */
+static inline move_t *moves_gen(move_t *moves, square_t from, bitboard_t to_bb)
+{
+    square_t to;
+    // bb_print(sq_to_string(from), to_bb);
+    while(to_bb) {
+        to = bb_next(&to_bb);
+        *moves++ = move_make(from, to);
+    }
+    return moves;
+}
+
+/**
+ * pos_gen_pseudo() - generate position pseudo-legal moves
  * @pos: position
  * @movelist: &movelist_t array to store pseudo-moves
  *
@@ -267,9 +337,9 @@ static inline move_t *move_make_promotions(move_t *moves, square_t from, square_
  *
  * TODO: move code to specific functions (especially castling, pawn push/capture)
  *
- * @Return: The total number of moves.
+ * @Return: movelist
  */
-int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
+movelist_t *pos_gen_pseudo(pos_t *pos, movelist_t *movelist)
 {
     color_t us               = pos->turn;
     color_t them             = OPPONENT(us);
@@ -289,12 +359,13 @@ int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
 
     //*nmoves = 0;
 
-    /* king - MUST BE FIRST (we stop if doubler check) */
+    /* king - MUST BE FIRST */
     to_bb = bb_king_moves(dest_squares, king);
-    while(to_bb) {
-        to = bb_next(&to_bb);
-        *moves++ = move_make(king, to);
-    }
+    moves = moves_gen(moves, king, to_bb);
+    //while(to_bb) {
+    //    to = bb_next(&to_bb);
+    //    *moves++ = move_make(king, to);
+    //}
 
     if (bb_multiple(pos->checkers))               /* double check, we stop here */
         goto finish;
@@ -334,19 +405,21 @@ int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
     while (from_bb) {
         from = bb_next(&from_bb);
         to_bb = hyperbola_bishop_moves(occ, from) & dest_squares;
-        while(to_bb) {
-            to = bb_next(&to_bb);
-            *moves++ = move_make(from, to);
-        }
+        moves = moves_gen(moves, from, to_bb);
+        //while(to_bb) {
+        //    to = bb_next(&to_bb);
+        //    *moves++ = move_make(from, to);
+        //}
     }
     from_bb = pos->bb[us][ROOK] | pos->bb[us][QUEEN];
     while (from_bb) {
         from = bb_next(&from_bb);
         to_bb = hyperbola_rook_moves(occ, from) & dest_squares;
-        while(to_bb) {
-            to = bb_next(&to_bb);
-            *moves++ = move_make(from, to);
-        }
+        moves = moves_gen(moves, from, to_bb);
+        //while(to_bb) {
+        //    to = bb_next(&to_bb);
+        //    *moves++ = move_make(from, to);
+        //}
     }
 
     /* knight */
@@ -354,10 +427,11 @@ int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
     while (from_bb) {
         from = bb_next(&from_bb);
         to_bb = bb_knight_moves(dest_squares, from);
-        while(to_bb) {
-            to = bb_next(&to_bb);
-            *moves++ = move_make(from, to);
-        }
+        moves = moves_gen(moves, from, to_bb);
+        //while(to_bb) {
+        //    to = bb_next(&to_bb);
+        //    *moves++ = move_make(from, to);
+        //}
     }
 
     /* pawn: relative rank and files */
@@ -378,7 +452,7 @@ int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
     while(to_bb) {
         to = bb_next(&to_bb);
         from = to - shift;
-        moves = move_make_promotions(moves, from, to);
+        moves = move_gen_promotions(moves, from, to);
     }
 
     /* possible second push */
@@ -386,66 +460,30 @@ int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
     while(to_bb) {
         to = bb_next(&to_bb);
         from = to - shift - shift;
-        *moves++ = move_make_flags(from, to, M_DPUSH);
+        //*moves++ = move_make_flags(from, to, M_DPUSH);
+        *moves++ = move_make(from, to);
     }
 
     /* pawn: captures */
-    /*
-     * tmp_bb = pawn_attacks_bb(pos->bb[us][PAWN], us) & enemy_pieces;
-     * //bb_print("FAIL", tmp_bb);
-     * to_bb = tmp_bb & ~rel_rank8;
-     * while (to_bb) {
-     *     to = bb_next(&to_bb);
-     *     from_bb = bb_pawn_attacks[them][to] & pos->bb[us][PAWN];
-     *     while (from_bb) {
-     *         from = bb_next(&from_bb);
-     *         *moves++ = move_make(from, to);
-     *     }
-     * }
-     * to_bb = tmp_bb & rel_rank8;
-     * while (to_bb) {
-     *     to = bb_next(&to_bb);
-     *     from_bb = bb_pawn_attacks[them][to] & pos->bb[us][PAWN];
-     *     while (from_bb) {
-     *         from = bb_next(&from_bb);
-     *         moves = move_make_promotions(moves, from, to);
-     *     }
-     * }
-     */
-
-    /* pawn: captures left */
-    bitboard_t filter = ~bb_rel_file(FILE_A, us);
-    shift = sq_upleft(us);
-    tmp_bb = bb_shift(pos->bb[us][PAWN] & filter, shift) & enemy_pieces;
-
+    tmp_bb = bb_pawns_attacks(pos->bb[us][PAWN], shift) & enemy_pieces;
+    //bb_print("FAIL", tmp_bb);
     to_bb = tmp_bb & ~rel_rank8;
     while (to_bb) {
         to = bb_next(&to_bb);
-        from = to - shift;
+        from_bb = bb_pawn_attacks[them][to] & pos->bb[us][PAWN];
+        while (from_bb) {
+            from = bb_next(&from_bb);
             *moves++ = move_make(from, to);
         }
+    }
     to_bb = tmp_bb & rel_rank8;
     while (to_bb) {
         to = bb_next(&to_bb);
-        from = to - shift;
-        moves = move_make_promotions(moves, from, to);
+        from_bb = bb_pawn_attacks[them][to] & pos->bb[us][PAWN];
+        while (from_bb) {
+            from = bb_next(&from_bb);
+            moves = move_gen_promotions(moves, from, to);
         }
-
-    /* pawn: captures right */
-    filter = ~bb_rel_file(FILE_H, us);
-    shift = sq_upright(us);
-    tmp_bb = bb_shift(pos->bb[us][PAWN] & filter, shift) & enemy_pieces;
-    to_bb = tmp_bb & ~rel_rank8;
-    while (to_bb) {
-        to = bb_next(&to_bb);
-        from = to - shift;
-        *moves++ = move_make(from, to);
-    }
-    to_bb = tmp_bb & rel_rank8;
-    while (to_bb) {
-        to = bb_next(&to_bb);
-        from = to - shift;
-        moves = move_make_promotions(moves, from, to);
     }
 
     /* pawn: en-passant
@@ -458,23 +496,11 @@ int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist)
             *moves++ = move_make_enpassant(from, to);
         }
     }
-    /*
-     * to_bb = mask(to);
-     *     /\* if e.p not on file H, we may add an e.p move to "up-left" *\/
-     *     filter = ~bb_rel_file(FILE_A, us);
-     *     shift = sq_upleft(us);
-     *     if (bb_shift(pos->bb[us][PAWN] & filter, shift) & to_bb)
-     *         *moves++ = move_make_enpassant(to - shift, to);
-     *
-     *     filter = ~bb_rel_file(FILE_H, us);
-     *     shift = sq_upright(us);
-     *     if (bb_shift(pos->bb[us][PAWN] & filter, shift) & to_bb)
-     *         *moves++ = move_make_enpassant(to - shift, to);
-     * }
-     */
 
     /* TODO: add function per piece, and type, for easier debug
      */
 finish:
-    return movelist->nmoves = moves - movelist->move;
+    movelist->nmoves = moves - movelist->move;
+    return movelist;
+    //return movelist->nmoves = moves - movelist->move;
 }

src/move-gen.h

@@ -23,7 +23,9 @@
 
 bool pseudo_is_legal(const pos_t *pos, const move_t move);
 move_t pos_next_legal(const pos_t *pos, movelist_t *movelist, int *start);
-movelist_t *pos_all_legal(const pos_t *pos, movelist_t *movelist, movelist_t *dest);
-int pos_gen_pseudomoves(pos_t *pos, movelist_t *movelist);
+movelist_t *pos_legal_dup(const pos_t *pos, movelist_t *pseudo, movelist_t *legal);
+movelist_t *pos_legal(const pos_t *pos, movelist_t *list);
+
+movelist_t *pos_gen_pseudo(pos_t *pos, movelist_t *movelist);
 
 #endif  /* MOVEGEN_H */

src/move.c

@@ -89,7 +89,7 @@
  */
 
 /**
- * move_str() - get a move string
+ * move_to_str() - get a move string
  * @dst: destination memory
  * @move: move
  * @flags: moves selection and display options.
@@ -102,7 +102,7 @@
  * M_PR_NL:    print a newline after move
  * M_PR_EVAL:  print move eval
  */
-char *move_str(char *dst, const move_t move, __unused const int flags)
+char *move_to_str(char *dst, const move_t move, __unused const int flags)
 {
     square_t from = move_from(move);
     square_t to   = move_to(move);
@@ -116,7 +116,6 @@ char *move_str(char *dst, const move_t move, __unused const int flags)
     return dst;
 }
 
-
 /**
  * moves_print() - print movelist moves.
  * @moves: &movelist_t moves list
@@ -135,7 +134,7 @@ void moves_print(movelist_t *moves, __unused int flags)
     char str[16];
     //printf("%2d:", moves->nmoves);
     for (int m = 0; m < moves->nmoves; ++m)
-        printf("%s ", move_str(str, moves->move[m], flags));
+        printf("%s ", move_to_str(str, moves->move[m], flags));
     printf("\n");
 }
 

src/move.h

@@ -42,30 +42,30 @@ enum {
     M_OFF_FROM     = 0,
     M_OFF_TO       = 6,
     M_OFF_PROMOTED = 12,
-    M_OFF_CAPTURED = 15,
-    M_OFF_FLAGS    = 18
+//    M_OFF_CAPTURED = 15,
+    M_OFF_FLAGS    = 15
 };
 
 typedef enum {
-    M_CAPTURE   = mask(M_OFF_FLAGS + 0),
-    M_ENPASSANT = mask(M_OFF_FLAGS + 1),
-    M_PROMOTION = mask(M_OFF_FLAGS + 2),
-    M_CASTLE_K  = mask(M_OFF_FLAGS + 3),          /* maybe only one ? */
-    M_CASTLE_Q  = mask(M_OFF_FLAGS + 5),          /* maybe only one ? */
-    M_CHECK     = mask(M_OFF_FLAGS + 6),          /* maybe unknown/useless ? */
-    M_DPUSH     = mask(M_OFF_FLAGS + 7)           /* pawn double push */
+    M_PROMOTION = 070000,
+//    M_CAPTURE   = BIT(M_OFF_FLAGS + 0),
+    M_ENPASSANT = BIT(M_OFF_FLAGS + 0),
+    M_CASTLE_K  = BIT(M_OFF_FLAGS + 1),           /* maybe only one ? */
+    M_CASTLE_Q  = BIT(M_OFF_FLAGS + 2),           /* maybe only one ? */
+    M_CHECK     = BIT(M_OFF_FLAGS + 3),           /* maybe unknown/useless ? */
+//    M_DPUSH     = BIT(M_OFF_FLAGS + 7)            /* pawn double push */
 } move_flags_t;
 
 #define move_set_flags(move, flags) ((move) | (flags))
 
-#define is_capture(m)   ((m) & M_CAPTURE)
+//#define is_capture(m)   ((m) & M_CAPTURE)
 #define is_enpassant(m) ((m) & M_ENPASSANT)
 #define is_promotion(m) ((m) & M_PROMOTION)
 #define is_castle(m)    ((m) & (M_CASTLE_K | M_CASTLE_Q))
 #define is_castle_K(m)  ((m) & M_CASTLE_K)
 #define is_castle_Q(m)  ((m) & M_CASTLE_Q)
 #define is_check(m)     ((m) & M_CHECK)
-#define is_dpush(m)     ((m) & M_DPUSH)
+//#define is_dpush(m)     ((m) & M_DPUSH)
 
 #define MOVES_MAX   256
 
@@ -89,10 +89,12 @@ static inline piece_type_t move_promoted(move_t move)
     return (move >> M_OFF_PROMOTED) & 07;
 }
 
-static inline piece_type_t move_captured(move_t move)
-{
-    return (move >> M_OFF_CAPTURED) & 07;
-}
+/*
+ * static inline piece_type_t move_captured(move_t move)
+ * {
+ *     return (move >> M_OFF_CAPTURED) & 07;
+ * }
+ */
 
 static inline move_t move_make(square_t from, square_t to)
 {
@@ -101,13 +103,16 @@ static inline move_t move_make(square_t from, square_t to)
 
 static inline move_t move_make_flags(square_t from, square_t to, move_flags_t flags)
 {
-    return move_set_flags(move_make(from, to), flags);
+    return (to << M_OFF_TO) | from | flags;
+    //move_set_flags(move_make(from, to), flags);
 }
 
-static inline move_t move_make_capture(square_t from, square_t to)
-{
-    return move_make_flags(from, to, M_CAPTURE);
-}
+/*
+ * static inline move_t move_make_capture(square_t from, square_t to)
+ * {
+ *     return move_make_flags(from, to, M_CAPTURE);
+ * }
+ */
 
 static inline move_t move_make_enpassant(square_t from, square_t to)
 {
@@ -117,19 +122,23 @@ static inline move_t move_make_enpassant(square_t from, square_t to)
 static inline move_t move_make_promote(square_t from, square_t to,
                                        piece_type_t promoted)
 {
-    return move_make_flags(from, to, M_PROMOTION) | (promoted << M_OFF_PROMOTED);
+    return move_make(from, to) | (promoted << M_OFF_PROMOTED);
 }
 
-static inline move_t move_make_promote_capture(square_t from, square_t to,
-                                               piece_type_t promoted)
-{
-    return move_make_promote(from, to, promoted) | M_CAPTURE;
-}
+/*
+ * static inline move_t move_make_promote_capture(square_t from, square_t to,
+ *                                                piece_type_t promoted)
+ * {
+ *     return move_make_promote(from, to, promoted) | M_CAPTURE;
+ * }
+ */
 
-static inline move_t move_set_captured(move_t move, piece_type_t captured)
-{
-    return move | (captured << M_OFF_CAPTURED);
-}
+/*
+ * static inline move_t move_set_captured(move_t move, piece_type_t captured)
+ * {
+ *     return move | (captured << M_OFF_CAPTURED);
+ * }
+ */
 
 /* moves_print flags
  */
@@ -143,7 +152,7 @@ static inline move_t move_set_captured(move_t move, piece_type_t captured)
 #define M_PR_LONG      0x80
 
 //int move_print(int movenum, move_t *move, move_flags_t flags);
-char *move_str(char *dst, const move_t move, __unused const int flags);
+char *move_to_str(char *dst, const move_t move, __unused const int flags);
 void moves_print(movelist_t *moves, int flags);
 void move_sort_by_sq(movelist_t *moves);
 

src/piece.c

@@ -78,8 +78,12 @@ char *piece_to_name(piece_t p)
 
 piece_type_t piece_t_from_char(char c)
 {
-    char *p = strchr(pieces_str, c);
-    return p? (p - pieces_str) % 6 + 1: NO_PIECE_TYPE;
+    char *p;
+    piece_type_t pt = NO_PIECE_TYPE;
+    if (c && (p = strchr(pieces_str, c))) {
+        pt = (p - pieces_str) % 6 + 1;
+    }
+    return pt;
 }
 
 //piece_type_t piece_from_promotion(char c, color_t color)

src/position.c

@@ -18,8 +18,8 @@
 #include <ctype.h>
 #include <assert.h>
 
-#include "brlib.h"
-#include "bitops.h"
+#include <brlib.h>
+#include <bitops.h>
 
 #include "chessdefs.h"
 #include "position.h"
@@ -62,9 +62,25 @@ pos_t *pos_dup(const pos_t *pos)
     return newpos;
 }
 
+/**
+ * pos_copy() - copy a position into another one.
+ * @from: &position to duplicate.
+ * @to: &destination position.
+ *
+ * Return a copy of @from into @to.
+ *
+ * @Return: @to.
+ */
+pos_t *pos_copy(const pos_t *from, pos_t *to)
+{
+    *to = *from;
+    return to;
+}
+
 /**
  * pos_del() - delete a position.
  * @pos: &position.
+ *
  */
 void pos_del(pos_t *pos)
 {
@@ -86,11 +102,12 @@ pos_t *pos_clear(pos_t *pos)
     pos->turn = WHITE;
 
     /* move_do/undo position state */
+    pos->key = 0;
     pos->en_passant = SQUARE_NONE;
     pos->castle = 0;
     pos->clock_50 = 0;
     pos->plycount = 0;
-    //pos->captured = NO_PIECE;
+    pos->captured = NO_PIECE;
 
     for (square_t sq = A1; sq <= H8; ++sq)
         pos->board[sq] = EMPTY;
@@ -106,7 +123,8 @@ pos_t *pos_clear(pos_t *pos)
     pos->pinners = 0;
     pos->blockers = 0;
 
-    //pos->moves.nmoves = 0;
+    pos->repeat.moves = 0;
+
     return pos;
 }
 
@@ -114,56 +132,45 @@ pos_t *pos_clear(pos_t *pos)
  * pos_cmp() - compare two positions..
  * @pos1, @pos2: The two &position.
  *
+ * Used only for move_{do,undo} test/debug.
+ *
  * @return: true if equal, false otherwise.
  */
-bool pos_cmp(__unused const pos_t *pos1, __unused const pos_t *pos2)
+bool pos_cmp(const pos_t *pos1, const pos_t *pos2)
 {
 #define _cmpf(a) (pos1->a != pos2->a)
     bool ret = false;
-    if (warn_on(_cmpf(node_count)))
-        goto end;
-    if (warn_on(_cmpf(turn)))
+
+    if (_cmpf(node_count) || _cmpf(turn))
         goto end;
 
     /* move_do/undo position state */
-    if (warn_on(_cmpf(en_passant)))
+    if (_cmpf(key) || _cmpf(en_passant) || _cmpf(castle) ||
+        _cmpf(clock_50) || _cmpf(plycount) || _cmpf(captured))
         goto end;
-    if (warn_on(_cmpf(castle)))
+
+    if (_cmpf(checkers) || _cmpf(pinners) || _cmpf(blockers))
         goto end;
-    if (warn_on(_cmpf(clock_50)))
-        goto end;
-    if (warn_on(_cmpf(plycount)))
-        goto end;
-    //if (warn_on(_cmpf(captured)))
-    //    goto end;
 
     for (square_t sq = A1; sq <= H8; ++sq)
-        if (warn_on(_cmpf(board[sq])))
+        if (_cmpf(board[sq]))
             goto end;
 
     for (color_t color = WHITE; color <= BLACK; ++color) {
-        for (piece_type_t piece = 0; piece <= KING; ++piece)
-            if (warn_on(_cmpf(bb[color][piece])))
+        for (piece_type_t piece = ALL_PIECES; piece <= KING; ++piece)
+            if (_cmpf(bb[color][piece]))
                 goto end;
-        //pos->controlled[color] = 0;
-        if (warn_on(_cmpf(king[color])))
+        if (_cmpf(king[color]))
             goto end;
     }
 
-    if (warn_on(_cmpf(checkers)))
-        goto end;
-    if (warn_on(_cmpf(pinners)))
-        goto end;
-    if (warn_on(_cmpf(blockers)))
+    if (_cmpf(checkers) ||_cmpf(pinners) || _cmpf(blockers))
         goto end;
 
-    /*
-     * if (warn_on(_cmpf(moves.nmoves)))
-     *     goto end;
-     * for (int i = 0; i < pos1->moves.nmoves; ++i)
-     *     if (warn_on(_cmpf(moves.move[i])))
-     *         goto end;
-     */
+    if (_cmpf(repeat.moves) ||
+        memcmp(pos1->repeat.key, pos2->repeat.key,
+               pos1->repeat.moves * sizeof pos1->repeat.key))
+        goto end;
 
     ret = true;
 end:
@@ -179,7 +186,7 @@ end:
  * Get a bitboard of all checkers on @color king.
  * Just a wrapper over @sq_attackers().
  *
- * @return: a bitboard of attackers.
+ * @return: a bitboard of checkers.
  */
 bitboard_t pos_checkers(const pos_t *pos, const color_t color)
 {
@@ -192,7 +199,7 @@ bitboard_t pos_checkers(const pos_t *pos, const color_t color)
  * @pos:   &position
  *
  * Set position checkers, pinners and blockers on player-to-play king.
- * It should be faster than @pos_checkers + @pos_set_pinners_blockers, as
+ * It should be slightly faster than @pos_checkers + @pos_set_pinners_blockers, as
  * some calculation will be done once.
  */
 void pos_set_checkers_pinners_blockers(pos_t *pos)
@@ -228,7 +235,7 @@ void pos_set_checkers_pinners_blockers(pos_t *pos)
         /* blockers = we find occupied squares between pinner and king */
         while (tmppinners) {
             pinner = bb_next(&tmppinners);
-            pinners |= mask(pinner);
+            pinners |= BIT(pinner);
             blockers |= bb_between[pinner][king] & maybeblockers;
         }
     }
@@ -246,7 +253,7 @@ void pos_set_checkers_pinners_blockers(pos_t *pos)
         tmppinners = targets & attackers;
         while (tmppinners) {
             pinner = bb_next(&tmppinners);
-            pinners |= mask(pinner);
+            pinners |= BIT(pinner);
             blockers |= bb_between[pinner][king] & maybeblockers;
         }
     }
@@ -336,11 +343,11 @@ bitboard_t pos_king_blockers(const pos_t *pos, const color_t color, const bitboa
  * - total number of pieces > 16 or zero (per color)
  * - number of kings != 1 (per color)
  * - discrepancy between board and king (per color)
- * - discrepancy between piece bitboards and ALL_PIECES bitboards (per color)
  * - discrepancy between bitboards and board (per color)
  * - side-to-move already checking opponent king
  * - side-to-move in check more than twice
  * - kings distance is 1
+ * - TODO: - castling / e.p. flags
  *
  * In case of errors, and @strict is true, @bug_on() is called, and program will
  * be terminated.
@@ -348,19 +355,25 @@ bitboard_t pos_king_blockers(const pos_t *pos, const color_t color, const bitboa
  * (eg after fen parsing), and with @strict == true otherwise (as we have some data
  * corruption).
  *
- * TODO: add more checks:
- * - kings attacking each other
- *
  * @return: (if @strict is false) return true if check is ok, false otherwise.
  */
-bool pos_ok(__unused const pos_t *pos, __unused const bool strict)
+bool pos_ok(pos_t *pos, const bool strict)
 {
     int n, count = 0, bbcount = 0, error = 0;
-    __unused bitboard_t tmp;
+    color_t us = pos->turn, them = OPPONENT(us);
+
+    /* force BUG_ON and WARN_ON */
+#   pragma push_macro("BUG_ON")
+#   pragma push_macro("WARN_ON")
+#   undef BUG_ON
+#   define BUG_ON
+#   undef WARN_ON
+#   define WARN_ON
+#   include <bug.h>
 
     /* pawns on 1st ot 8th rank */
-    tmp = (pos->bb[WHITE][PAWN] | pos->bb[BLACK][PAWN]) & (RANK_1bb | RANK_8bb);
-    error += warn_on(tmp);
+    error += warn_on((pos->bb[WHITE][PAWN] | pos->bb[BLACK][PAWN]) &
+                     (RANK_1bb | RANK_8bb));
 
     for (color_t color = WHITE; color <= BLACK; ++color) {
         /* pawn count */
@@ -378,26 +391,33 @@ bool pos_ok(__unused const pos_t *pos, __unused const bool strict)
     }
     for (square_t sq = 0; sq < 64; ++sq) {
         piece_t piece = pos->board[sq];
-        __unused bitboard_t match;
+        bitboard_t match;
         if (piece == EMPTY)
             continue;
         color_t c = COLOR(piece);
         piece_type_t p = PIECE(piece);
-        match = pos->bb[c][p] & mask(sq);
+        match = pos->bb[c][p] & BIT(sq);
         error += warn_on(!match);
         count++;
     }
-    /* occupied occupation is different from bitboards */
+    /* occupied board is different from bitboards */
     error += warn_on(count != bbcount);
     /* is opponent already in check ? */
-    error += warn_on(pos_checkers(pos, OPPONENT(pos->turn)));
+    error += warn_on(pos_checkers(pos, them));
     /* is color to play in check more than twice ? */
-    error += warn_on(popcount64(pos_checkers(pos, OPPONENT(pos->turn))) > 2);
+    error += warn_on(popcount64(pos_checkers(pos, us)) > 2);
     /* kings distance is less than 2 */
     error += warn_on(sq_dist(pos->king[WHITE], pos->king[BLACK]) < 2);
+    /* e.p. and castling rights check */
+    error += fen_ok(pos, false);
 
-    bug_on(strict && error);
+    if (strict) {
+        bug_on(error);
+        /* not reached */
+    }
     return error? false: true;
+#   pragma pop_macro("WARN_ON")
+#   pragma pop_macro("BUG_ON")
 }
 
 /**
@@ -409,9 +429,10 @@ void pos_print(const pos_t *pos)
     char str[128];
 
     board_print(pos->board);
-    printf("fen %s\n", pos2fen(pos, str));
-    printf("checkers: %s\n", pos_checkers2str(pos, str, sizeof(str)));
-    printf("pinners : %s\n", pos_pinners2str(pos, str, sizeof(str)));
+    printf("key:%lx ", pos->key);
+    printf("fen: %s\n", pos2fen(pos, str));
+    printf("checkers:%s ", pos_checkers2str(pos, str, sizeof(str)));
+    printf("pinners: %s ", pos_pinners2str(pos, str, sizeof(str)));
     printf("blockers: %s\n", pos_blockers2str(pos, str, sizeof(str)));
 }
 

src/position.h

@@ -16,43 +16,55 @@
 
 #include <stdint.h>
 
-#include "brlib.h"
-#include "bitops.h"
-#include "struct-group.h"
+#include <brlib.h>
+#include <bitops.h>
+#include <struct-group.h>
+#include <bug.h>
 
 #include "chessdefs.h"
+#include "hash.h"
 #include "bitboard.h"
 #include "piece.h"
 #include "move.h"
 #include "board.h"
 
+#define REPEAT_SIZE 1024
+
+typedef struct {
+    hkey_t key[REPEAT_SIZE];
+    int moves;
+} repeat_t;
+
 typedef struct __pos_s {
     u64 node_count;                               /* evaluated nodes */
     int turn;                                     /* WHITE or BLACK */
 
-    /* data which cannot be recovered by move_undo (like castle_rights, ...),
-     * or would be expensive to recover (checkers, ...)
-     * following data can be accessed either directly, either via "movesave"
+    /* data which cannot be recovered by move_undo (like castle_rights, ...).
+     *
+     * Attention: checkers/pinners/blockers are not included here, and
+     * are not available in move_undo or any following legality check.
+     *
+     * Following data can be accessed either directly, either via "state"
      * structure name.
      * For example, pos->en_passant and pos->state.en_passant are the same.
      * This allows a memcpy on this data (to save/restore position state).
      */
     struct_group_tagged(state_s, state,
+                        hkey_t key;
                         square_t en_passant;
                         castle_rights_t castle;
-                        u16 clock_50;
-                        u16 plycount;             /* plies so far, start from 1 */
-                        piece_t captured;         /* only for move_undo */
+                        int clock_50;
+                        int plycount;             /* plies so far, start from 1 */
+                        piece_t captured;         /* only used in move_undo */
+        );
     bitboard_t checkers;                          /* opponent checkers */
     bitboard_t pinners;                           /* opponent pinners */
     bitboard_t blockers;                          /* pieces blocking pin */
-        );
 
     piece_t board[BOARDSIZE];
     bitboard_t bb[2][PIECE_TYPE_MAX];             /* bb[0][PAWN], bb[1][ALL_PIECES] */
-    //bitboard_t controlled[2];                     /* unsure */
     square_t king[2];                             /* dup with bb, faster retrieval */
-    //movelist_t moves;
+    repeat_t repeat;                              /* for repetition detection */
 } pos_t;
 
 typedef struct state_s state_t;
@@ -71,11 +83,16 @@ static __always_inline void pos_set_sq(pos_t *pos, square_t square, piece_t piec
 {
     color_t color = COLOR(piece);
     piece_type_t type = PIECE(piece);
+
+    bug_on(pos->board[square] != EMPTY);
+
     pos->board[square] = piece;
-    pos->bb[color][type] |= mask(square);
-    pos->bb[color][ALL_PIECES] |= mask(square);
-    if (type == KING)
-        pos->king[color] = square;
+    pos->bb[color][type] |= BIT(square);
+    pos->bb[color][ALL_PIECES] |= BIT(square);
+    //if (type == KING)
+    //    pos->king[color] = square;
+
+    //pos->key ^= zobrist_pieces[piece][square];
 }
 
 /**
@@ -90,11 +107,16 @@ static __always_inline void pos_clr_sq(pos_t *pos, square_t square)
     piece_t piece = pos->board[square];
     piece_type_t type = PIECE(piece);
     color_t color = COLOR(piece);
+
+    bug_on(pos->board[square] == EMPTY);
+
+    //pos->key ^= zobrist_pieces[piece][square];
+
     pos->board[square] = EMPTY;
-    pos->bb[color][type] &= ~mask(square);
-    pos->bb[color][ALL_PIECES] &= ~mask(square);
-    if (type == KING)
-        pos->king[color] = SQUARE_NONE;
+    pos->bb[color][type] &= ~BIT(square);
+    pos->bb[color][ALL_PIECES] &= ~BIT(square);
+    //if (type == KING)
+    //    pos->king[color] = SQUARE_NONE;
 }
 
 /**
@@ -155,6 +177,7 @@ static __always_inline int pos_between_count(const pos_t *pos,
 
 pos_t *pos_new();
 pos_t *pos_dup(const pos_t *pos);
+pos_t *pos_copy(const pos_t *from, pos_t *to);
 void pos_del(pos_t *pos);
 pos_t *pos_clear(pos_t *pos);
 bool pos_cmp(const pos_t *pos1, const pos_t *pos2);
@@ -165,7 +188,7 @@ bitboard_t pos_checkers(const pos_t *pos, const color_t color);
 bitboard_t pos_king_pinners(const pos_t *pos, const color_t color);
 bitboard_t pos_king_blockers(const pos_t *pos, const color_t color, const bitboard_t );
 
-bool pos_ok(const pos_t *pos, const bool strict);
+bool pos_ok(pos_t *pos, const bool strict);
 
 void pos_print(const pos_t *pos);
 void pos_print_mask(const pos_t *pos, const bitboard_t mask);

src/search.c

@@ -33,49 +33,85 @@
  * This version uses the algorithm:
  *    if last depth
  *      return 1;
- *    gen pseudo-legal moves
- *    loop for each legal move
+ *    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)
+u64 perft(pos_t *pos, int depth, int ply, bool output)
 {
-    int subnodes, movetmp = 0;
-    u64 nodes = 0;
-    movelist_t pseudo;
-    move_t move;
+    static movelist_t stack;
+    //int subnodes;
+    u64 subnodes, nodes = 0;
+    movelist_t movelist;
+    move_t *move, *last;
     state_t state;
 
-    if (depth == 0)
-        return 1;
-    pseudo.nmoves = 0;
-    pos->checkers = pos_checkers(pos, pos->turn);
-    pos_set_pinners_blockers(pos);
-    state = pos->state;
+    if (ply == 1)
+        stack.nmoves = 0;
 
-    pos_gen_pseudomoves(pos, &pseudo);
-    while ((move =  pos_next_legal(pos, &pseudo, &movetmp)) != MOVE_NONE) {
-        move_do(pos, move);
-        subnodes = perft(pos, depth - 1, ply + 1);
-        if (ply == 1) {
+    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) {
+            nodes++;
+        } else {
+            move_do(pos, *move, &state);
+            stack.move[stack.nmoves++] = *move;
+            if (ply == 2 &&
+                //move_from(*move) == F7 &&
+                //move_to(*move) == F5 &&
+                move_from(stack.move[stack.nmoves-2]) == B2 &&
+                move_to(stack.move[stack.nmoves-2]) == B4 &&
+                move_from(stack.move[stack.nmoves-1]) == F7 &&
+                move_to(stack.move[stack.nmoves-1]) == F5
+                ) {
+                //&& pos->board[F5] == B_PAWN) {
+                moves_print(&stack, 0);
+                pos_print(pos);
+            }
+            if (depth == 2) {
+                movelist_t movelist2;
+                pos_set_checkers_pinners_blockers(pos);
+                subnodes = pos_legal(pos, pos_gen_pseudo(pos, &movelist2))->nmoves;
+            } else {
+                hentry_t *entry;
+                //if (ply >= 4 && ply <= 8) {
+                if (ply == 4) {
+                    if ((entry = tt_probe_perft(pos->key, depth))) {
+                        subnodes = HASH_PERFT_VAL(entry->data);
+                        printf("tt hit key=%lx ply=%d depth=%d nodes=%lu\n",
+                               pos->key, ply, depth, subnodes);
+                    } else {
+                        subnodes = perft(pos, depth - 1, ply + 1, output);
+                        tt_store_perft(pos->key, depth, subnodes);
+                    }
+                } else {
+                    subnodes = perft(pos, depth - 1, ply + 1, output);
+                }
+            }
+            if (output && ply == 1) {
                 char movestr[8];
-            printf("%s: %d\n", move_str(movestr, move, 0), subnodes);
+                printf("%s: %lu\n", move_to_str(movestr, *move, 0), subnodes);
             }
             nodes += subnodes;
-        move_undo(pos, move);
-        pos->state = state;
+            move_undo(pos, *move, &state);
+            stack.nmoves--;
+        }
     }
 
-    if (ply == 1)
+    if (output && ply == 1)
         printf("Total: %lu\n", nodes);
     return nodes;
 }
 
 /**
- * perft_new_pinners() - Perform perft on position
+ * perft_alt() - Perform perft on position, experimental version.
  * @pos:   &position to search
  * @depth: Wanted depth.
  * @ply:   perft depth level.
@@ -85,34 +121,43 @@ u64 perft(pos_t *pos, int depth, int ply)
  *
  * @return: total moves found at @depth level.
  */
-u64 perft_new_pinners(pos_t *pos, int depth, int ply)
+u64 perft_alt(pos_t *pos, int depth, int ply, bool output)
 {
-    int subnodes, movetmp = 0;
+    int subnodes;
     u64 nodes = 0;
-    movelist_t pseudo;
-    move_t move;
+    movelist_t movelist;
+    move_t *move, *last;
     state_t state;
 
-    if (depth == 0)
-        return 1;
-    pseudo.nmoves = 0;
+    //movelist.nmoves = 0;
     pos_set_checkers_pinners_blockers(pos);
     state = pos->state;
 
-    pos_gen_pseudomoves(pos, &pseudo);
-    while ((move =  pos_next_legal(pos, &pseudo, &movetmp)) != MOVE_NONE) {
-        move_do(pos, move);
-        subnodes = perft_new_pinners(pos, depth - 1, ply + 1);
-        if (ply == 1) {
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+    last = movelist.move + movelist.nmoves;
+    for (move = movelist.move; move < last; ++move) {
+        if (depth == 1) {
+            nodes++;
+        } else {
+            move_do_alt(pos, *move);
+            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, output);
+            }
+            if (output && ply == 1) {
                 char movestr[8];
-            printf("%s: %d\n", move_str(movestr, move, 0), subnodes);
+                printf("%s: %d\n", move_to_str(movestr, *move, 0), subnodes);
             }
             nodes += subnodes;
-        move_undo(pos, move);
+            move_undo_alt(pos, *move);
             pos->state = state;
         }
+    }
 
-    if (ply == 1)
+    if (output && ply == 1)
         printf("Total: %lu\n", nodes);
     return nodes;
 }

src/search.h

@@ -19,8 +19,7 @@
 //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);
-u64 perft2(pos_t *pos, int depth, int ply);
-u64 perft_new_pinners(pos_t *pos, int depth, int ply);
+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/util.h

@@ -17,13 +17,19 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-#include "bug.h"
+#include <bug.h>
 
 #include "chessdefs.h"
 
 #undef safe_malloc
 #undef safe_free
 
+/* force BUG_ON, to get a program abort for failed malloc/free
+ */
+#pragma push_macro("BUG_ON")
+#undef BUG_ON
+#define BUG_ON
+
 #define safe_malloc(size) ({                   \
             void *_ret = malloc(size);         \
             bug_on(_ret == NULL);              \
@@ -35,4 +41,8 @@
         free(ptr);                             \
     } while (0)
 
+/* restore BUG_ON
+ */
+#pragma pop_macro("BUG_ON")
+
 #endif  /* UTIL_H */

test/common-test.h

@@ -28,15 +28,30 @@ struct fentest {
     char *comment;
     char *fen;
 } fentest[] = {
+    /******************* TEMP TESTS BELOW *******************/
+
     /*
-    { __LINE__.
-      ATTACK,
-      "checkers: ",
-      ""
-    },
+     * { __LINE__, MOVEGEN | MOVEDO | PERFT,
+     *   "bug perft TT après 1.b4 f5",
+     *   "1nbqkbn1/ppp1p1pp/8/r1rpPpK1/1P6/8/P1PP1PPP/RNBQ1BNR w - f6 0 2"
+     * },
      */
 
-/* ***************** TEMP TESTS ABOVE ************************** */
+    /*
+     * { __LINE__, MOVEGEN | MOVEDO | PERFT,
+     *   "bug perft TT après 1.b4",
+     *   "1nbqkbn1/ppp1pppp/8/r1rpP1K1/1P6/8/P1PP1PPP/RNBQ1BNR b - - 0 1",
+     * },
+     */
+
+    { __LINE__, MOVEGEN | MOVEDO | PERFT,
+      "bug perft TT",
+      "1nbqkbn1/ppp1pppp/8/r1rpP1K1/8/8/PPPP1PPP/RNBQ1BNR w - d6 0 1",
+    },
+
+    /* ***************** END of TEMP TESTS ******************/
+    /* below line ignored if first test */
+    { __LINE__, 0, NULL, NULL },
 
     { __LINE__, MOVEGEN | MOVEDO | PERFT,
       "illegal white e.p.",
@@ -394,6 +409,14 @@ struct fentest {
       "simple movedo/undo: only 2 W knights",
       "5n2/1k6/8/8/5K2/8/P7/1N6 w - - 0 1"
     },
+    { __LINE__, FEN,
+      "legal EP",
+      "4k3/8/8/3pP3/8/8/8/4K3 w - d6 0 1"
+    },
+    { __LINE__, FEN,
+      "illegal EP, fix-able by fen parser",
+      "4k3/8/8/3p1P2/8/8/8/4K3 w - d6 0 1"
+    },
     { __LINE__, FEN,
       "illegal EP and castle flags, fix-able by fen parser, SF crash",
       "4k3/8/8/8/7B/8/8/4K3 w KQkq e6 0 1"
@@ -413,22 +436,26 @@ struct fentest {
     { __LINE__, 0, NULL, NULL }
 };
 
-static int cur = -1;
+static int fentest_cur = -1;
 
 static char *next_fen(uint module)
 {
-    cur++;
-    while (fentest[cur].fen && !(fentest[cur].modules & module))
-        cur++;
-    return fentest[cur].fen;
+    fentest_cur++;
+
+    /* skip first entry if NULL - for special testing, see  */
+    if (fentest_cur == 0 && fentest[fentest_cur].fen == NULL)
+        fentest_cur++;
+    while (fentest[fentest_cur].fen && !(fentest[fentest_cur].modules & module))
+        fentest_cur++;
+    return fentest[fentest_cur].fen;
 }
 
 static __unused char* cur_comment()
 {
-    return fentest[cur].comment;
+    return fentest[fentest_cur].comment;
 }
 
 static __unused int cur_line()
 {
-    return fentest[cur].line;
+    return fentest[fentest_cur].line;
 }

test/fen-test.c

@@ -31,8 +31,7 @@ int main(__unused int ac, __unused char**av)
     bitboard_init();
 
     while ((fen = next_fen(FEN))) {
-        printf("***** [%s] ", fen);
-        fflush(stdout);
+        printf("line %3d: [%s] ", cur_line(), fen);
         if (!(pos = fen2pos(NULL, fen))) {
             printf("**INVALID\n");
         } else {

test/movedo-test.c

@@ -29,13 +29,10 @@ int main(int __unused ac, __unused char**av)
     int i = 0, test_line;
     char *fen, movebuf[8];;
     pos_t *pos, *savepos;
-    movelist_t pseudo;
-    move_t move;
+    movelist_t movelist;
+    move_t *move, *last;
 
-    setlinebuf(stdout);                           /* line-buffered stdout */
-
-    bitboard_init();
-    hyperbola_init();
+    init_all();
 
     while ((fen = next_fen(MOVEDO))) {
         test_line = cur_line();
@@ -44,39 +41,39 @@ int main(int __unused ac, __unused char**av)
             continue;
         }
 
-        pos->checkers = pos_checkers(pos, pos->turn);
-        pos_set_pinners_blockers(pos);
-
-        pos_gen_pseudomoves(pos, &pseudo);
+        movelist.nmoves = 0;
+        pos_set_checkers_pinners_blockers(pos);
+        pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+        last = movelist.move + movelist.nmoves;
         savepos = pos_dup(pos);
 
         state_t state = pos->state;
-        int tmp = 0, j = 0;
-        while ((move = pos_next_legal(pos, &pseudo, &tmp)) != MOVE_NONE) {
+        int j = 0;
+        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_do(pos, move);
+            move_do(pos, *move, &state);
             //pos_print(pos);
             //fflush(stdout);
             if (!pos_ok(pos, false)) {
-                printf("*** fen %d move %d [%s] invalid position after move_do\n",
-                       test_line, j, movebuf);
+                printf("*** fen %d [%s] move %d [%s] invalid position after move_do\n",
+                       test_line, fen, j, move_to_str(movebuf, *move, 0));
                 exit(0);
             }
 
             //printf("%d/%d move_do check ok\n", i, j);
-            move_undo(pos, move);
+            move_undo(pos, *move, &state);
             pos->state = state;
             if (!pos_ok(pos, false)) {
-                printf("*** fen %d move %d [%s] invalid position after move_undo\n",
-                       test_line, j, movebuf);
+                printf("*** fen %d [%s] move %d [%s] invalid position after move_undo\n",
+                       test_line, fen, j, movebuf);
                 exit(0);
             }
             if (pos_cmp(pos, savepos) != true) {
-                printf("*** fen %d move %d [%s] position differ after move_{do,undo}\n",
-                       test_line, j, movebuf);
+                printf("*** fen %d [%s] move %d [%s] position differ after move_{do,undo}\n",
+                       test_line, fen, j, movebuf);
                 exit(0);
             }
             //fflush(stdout);

test/movegen-test.c

@@ -216,7 +216,7 @@ int main(int __unused ac, __unused char**av)
     FILE *outfd;
     char *fen;
     pos_t *pos, *fishpos = pos_new();
-    movelist_t pseudo, legal, fishmoves;
+    movelist_t pseudo, fishmoves;
     //bitboard_t wrong = 0x5088000040, tmp, loop;
     //bit_for_each64(loop, tmp, )
     //printf("fishpos 1=%p\n", fishpos);
@@ -239,9 +239,9 @@ int main(int __unused ac, __unused char**av)
         send_stockfish_fen(outfd, fishpos, &fishmoves, fen);
 
         pos_set_checkers_pinners_blockers(pos);
-        pos_gen_pseudomoves(pos, &pseudo);
+        pos_gen_pseudo(pos, &pseudo);
         //moves_print(&pseudo, 0);
-        pos_all_legal(pos, &pseudo, &legal);
+        pos_legal(pos, &pseudo);
 
         //moves_print(&legal, 0);
         //printf("Fu ");
@@ -253,7 +253,7 @@ int main(int __unused ac, __unused char**av)
 
         /* sort and print movelists */
         move_sort_by_sq(&fishmoves);
-        move_sort_by_sq(&legal);
+        move_sort_by_sq(&pseudo);
         // printf("\nFs ");
         // moves_print(fishpos, 0);
         // fflush(stdout);
@@ -262,14 +262,14 @@ int main(int __unused ac, __unused char**av)
         // fflush(stdout);
 
         /* compare movelists */
-        if (!movelists_equal(&fishmoves, &legal)) {
+        if (!movelists_equal(&fishmoves, &pseudo)) {
             pos_print(pos);
             printf("F: ");
             moves_print(&fishmoves, 0);
             printf("M: ");
-            moves_print(&legal, 0);
+            moves_print(&pseudo, 0);
         } else {
-            printf("[%s]: OK (%d Moves)\n", fen, legal.nmoves);
+            printf("[%s]: OK (%d Moves)\n", fen, pseudo.nmoves);
             //moves_print(&fishpos->moves, 0);
         }
         //compare_moves(&fishpos->moves, &legal);

test/perft-test.c

@@ -16,6 +16,7 @@
 #include <unistd.h>
 #include <time.h>
 #include <locale.h>
+#include <limits.h>
 
 #include "chessdefs.h"
 #include "fen.h"
@@ -43,6 +44,9 @@ static FILE *open_stockfish()
     int rpipe[2], wpipe[2];
     FILE *out_desc;
     pid_t pid;
+    char *buf = NULL;
+    size_t alloc = 0;
+    ssize_t buflen;
 
     if ((pipe(rpipe) < 0) || (pipe(wpipe) < 0)) {
         perror("pipe");
@@ -83,11 +87,36 @@ static FILE *open_stockfish()
     out_desc = fdopen(wpipe[WR], "w");
     setvbuf(out_desc, NULL, _IOLBF, 0);
 
+    fprintf(out_desc, "uci\n");
+    while (true) {
+        if ((buflen = getline(&buf, &alloc, stdin)) < 0) {
+            perror("getline");
+            exit(1);
+        }
+        if (!strncmp(buf, "uciok", 5))
+            break;
+    }
+    free(buf);
     return out_desc;
 }
 
-static u64 send_stockfish_fen(FILE *desc, pos_t *pos, movelist_t *movelist,
-                               char *fen, int depth)
+static void stockfish_fen(FILE *desc, char *fen)
+{
+    char *buf = NULL;
+    size_t alloc = 0;
+    ssize_t buflen;
+
+    fprintf(desc, "ucinewgame\nisready\n");
+    while ((buflen = getline(&buf, &alloc, stdin)) > 0) {
+        if (!strncmp(buf, "readyok", 7))
+            break;
+    }
+    fprintf(desc, "position fen %s\n", fen);
+    free(buf);
+}
+
+static u64 stockfish_perft(FILE *desc, pos_t *pos, movelist_t *movelist,
+                               int depth)
 {
     char *buf = NULL;
     u64 count, mycount = 0, fishcount;
@@ -101,10 +130,12 @@ static u64 send_stockfish_fen(FILE *desc, pos_t *pos, movelist_t *movelist,
     *nmoves = 0;
     //char nodescount[] = "Nodes searched";
     //printf("nmoves = %d\n", nmoves);
-    fflush(stdout);
+    //fflush(stdout);
     //sprintf(str, "stockfish \"position fen %s\ngo perft depth\n\"", fen);
-    fprintf(desc, "position fen %s\ngo perft %d\n", fen, depth);
+    //fprintf(desc, "position fen %s\ngo perft %d\n", fen, depth);
     //fflush(desc);
+    fprintf(desc, "go perft %d\n", depth);
+
     while ((buflen = getline(&buf, &alloc, stdin)) > 0) {
         buf[--buflen] = 0;
         if (buflen == 0)
@@ -222,73 +253,154 @@ static __unused void compare_moves(movelist_t *fish, movelist_t *me)
     printf("F(%2d): %s\nM(%2d): %s\n", n1, str1, n2, str2);
 }
 
-
-int main(int __unused ac, __unused char**av)
+static int usage(char *prg)
 {
-    int i = 0, test_line;
-    u64 sf_count, my_count;
+    fprintf(stderr, "Usage: %s [-cmv][-d depth] [-p perft-version] \n", prg);
+    fprintf(stderr, "\t-c/m: print comments/moves, -n: no SF check, -d: depth, -p: 1-3, \n");
+    return 1;
+}
+
+int main(int ac, char**av)
+{
+    int test_line;
+    u64 sf_count = 0, my_count;
+    bool comment = false;
     char *fen;
-    pos_t *pos, *savepos, *fishpos = pos_new();
+    pos_t *pos = NULL, *fenpos;
+    pos_t *fishpos = pos_new();
     movelist_t fishmoves;
-    //move_t move;
-    FILE *outfd;
-    s64 ms1 = 0, ms1_total = 0;
-    s64 ms2 = 0, ms2_total = 0;
+    FILE *outfd = NULL;
+    struct {
+        s64 count, ms;
+        s64 minlps, maxlps;
+        int skipped;
+    } res[3] = {
+        { .minlps=LONG_MAX },
+        { .minlps=LONG_MAX },
+        { .minlps=LONG_MAX },
+    };
+    s64 ms, lps;
 
-    int depth = 6, run = 3;
+    int opt, depth = 6, run = 3;
+    bool sf_run = true, perft_output = false;
 
-    if (ac > 1)
-        depth = atoi(av[1]);
-    if (ac > 2)
-        run =  atoi(av[2]) & 3;
-    printf("depth = %d run=%d\n", depth, run);
+    while ((opt = getopt(ac, av, "cmnd:p:")) != -1) {
+        switch (opt) {
+            case 'c':
+                comment = true;
+                break;
+            case 'd':
+                depth = atoi(optarg);
+                break;
+            case 'p':                             /* 1 or 2 or 3 for both */
+                run = atoi(optarg);
+                break;
+            case 'n':
+                sf_run = false;
+                break;
+            case 'm':
+                perft_output = true;
+                break;
+            default:
+                    return usage(*av);
+        }
+    }
+
+    printf("perft: depth = %d run = %x stockfish = %s\n",
+           depth, run, sf_run? "true": "false");
+
+    init_all();
 
     if (!run)
         exit(0);
-    setlocale(LC_NUMERIC, "");
-    setlinebuf(stdout);                           /* line-buffered stdout */
+
+    if (sf_run)
         outfd = open_stockfish();
 
-    bitboard_init();
-    hyperbola_init();
-
-    CLOCK_DEFINE(clock, CLOCK_PROCESS);
+    CLOCK_DEFINE(clock, CLOCK_MONOTONIC);
     while ((fen = next_fen(PERFT | MOVEDO))) {
+        if (comment)
+            printf("%s\n", *cur_comment()? cur_comment(): "<FIXME>");
         test_line = cur_line();
-        if (!(pos = fen2pos(NULL, fen))) {
-            printf("wrong fen %d: [%s]\n", i, fen);
+        tt_clear();
+        if (!(fenpos = fen2pos(pos, fen))) {
+            printf("wrong fen line = %d: [%s]\n", test_line, fen);
             continue;
         }
-        sf_count = send_stockfish_fen(outfd, fishpos, &fishmoves, fen, depth);
-        savepos = pos_dup(pos);
+        pos = fenpos;
+        if (sf_run) {
+            stockfish_fen(outfd, fen);
+            clock_start(&clock);
+            sf_count = stockfish_perft(outfd, fishpos, &fishmoves, depth);
+            ms = clock_elapsed_ms(&clock);
+            if (!ms) {
+                res[2].skipped++;
+                lps = 0;
+            } else {
+                lps = sf_count * 1000l / ms;
+                res[2].ms += ms;
+                res[2].count += sf_count;
+                if (lps > res[2].maxlps)
+                    res[2].maxlps = lps;
+                if (lps < res[2].minlps)
+                    res[2].minlps = lps;
+            }
+            printf("SF     : line=%3d perft=%'lu %'ldms lps=%'lu \"%s\"\n",
+                   test_line, sf_count, ms,
+                   lps,
+                   fen);
+        }
 
         if (run & 1) {
             clock_start(&clock);
-            my_count = perft(pos, depth, 1);
-            ms1 = clock_elapsed_ms(&clock);
-            ms1_total += ms1;
+            my_count = perft(pos, depth, 1, perft_output);
+            ms = clock_elapsed_ms(&clock);
+            if (!ms) {
+                res[0].skipped++;
+                lps = 0;
+            } else {
+                lps = my_count * 1000l / ms;
+                res[0].ms += ms;
+                res[0].count += my_count;
+                if (lps > res[0].maxlps)
+                    res[0].maxlps = lps;
+                if (lps < res[0].minlps)
+                    res[0].minlps = lps;
+            }
 
-            if (sf_count == my_count) {
+            if (!sf_run || sf_count == my_count) {
                 printf("pt1 OK : line=%3d perft=%'lu %'ldms lps=%'lu \"%s\"\n",
-                       test_line, my_count, ms1,
-                       ms1? my_count*1000l/ms1: 0,
+                       test_line, my_count, ms,
+                       lps,
                        fen);
             } else  {
                 printf("pt1 ERR: line=%3d sf=%'lu me=%'lu \"%s\"\n",
                        test_line, sf_count, my_count, fen);
             }
+            tt_stats();
         }
 
         if (run & 2) {
             clock_start(&clock);
-            my_count = perft_new_pinners(pos, depth, 1);
-            ms2 = clock_elapsed_ms(&clock);
-            ms2_total += ms2;
+            my_count = perft_alt(pos, depth, 1, perft_output);
+            ms = clock_elapsed_ms(&clock);
+            if (!ms) {
+                res[1].skipped++;
+                lps = 0;
+            } else {
+                lps = my_count * 1000l / ms;
+                res[1].ms += ms;
+                res[1].count += my_count;
+                if (lps > res[1].maxlps)
+                    res[1].maxlps = lps;
+                if (lps < res[1].minlps)
+                    res[1].minlps = lps;
+            }
 
-            if (sf_count == my_count) {
+            if (!sf_run || sf_count == my_count) {
                 printf("pt2 OK : line=%3d perft=%'lu %'ldms lps=%'lu \"%s\"\n",
-                       test_line, my_count, ms2,
-                       ms2? my_count*1000l/ms2: 0,
+                       test_line, my_count, ms,
+                       lps,
                        fen);
             } else  {
                 printf("pt2 ERR: line=%3d sf=%'lu me=%'lu \"%s\"\n",
@@ -296,15 +408,34 @@ int main(int __unused ac, __unused char**av)
             }
         }
         printf("\n");
-        pos_del(savepos);
-        pos_del(pos);
-        i++;
-        /* to run first test only */
-        // exit(0);
     }
-    if (run & 1)
-        printf("total perft  %'ldms\n", ms1_total);
-    if (run & 2)
-        printf("total perft2 %'ldms\n", ms2_total);
+    pos_del(pos);
+    if (sf_run) {
+        if (!res[2].ms)
+            res[2].ms = 1;
+        printf("total SF     %'lums %'lums lps=%'lu min=%'lu max=%'lu (skipped %d)\n",
+               res[2].count, res[2].ms,
+               res[2].count * 1000l / res[2].ms,
+               res[2].minlps, res[2].maxlps,
+               res[2].skipped);
+    }
+    if (run & 1) {
+        if (!res[0].ms)
+            res[0].ms = 1;
+        printf("total perft  %'lums %'lums lps=%'lu min=%'lu max=%'lu (skipped %d)\n",
+               res[0].count, res[0].ms,
+               res[0].count * 1000l / res[0].ms,
+               res[0].minlps, res[0].maxlps,
+               res[0].skipped);
+    }
+    if (run & 2) {
+        if (!res[1].ms)
+            res[1].ms = 1;
+        printf("total perft2 %'lums %'lums lps=%'lu min=%'lu max=%'lu (skipped %d)\n",
+               res[1].count, res[1].ms,
+               res[1].count * 1000l / res[1].ms,
+               res[1].minlps, res[1].maxlps,
+               res[1].skipped);
+    }
     return 0;
 }

test/tt-test.c

@@ -0,0 +1,159 @@
+/* tt-test.c - transposition table test.
+ *
+ * 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 <stdlib.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <time.h>
+#include <locale.h>
+#include <limits.h>
+
+#include <brlib.h>
+
+#include "chessdefs.h"
+#include "fen.h"
+#include "position.h"
+#include "move.h"
+#include "move-do.h"
+#include "move-gen.h"
+#include "search.h"
+
+// #include "common-test.h"
+
+static move_t move_in_movelist(movelist_t *ml, square_t from, square_t to, piece_type_t pt)
+{
+    const int nmoves = ml->nmoves;
+    const move_t *moves = ml->move;
+    int movenum = 0;
+    move_t move;
+    for (movenum = 0; movenum < nmoves; ++movenum) {
+        move = moves[movenum];
+        printf("compare %s%s to %s%s pt=%d ",
+               sq_to_string(from), sq_to_string(to),
+               sq_to_string(move_from(move)),
+               sq_to_string(move_to(move)),
+               pt
+            );
+        if (move_from(move) == from && move_to(move) == to) {
+            printf("HIT!\n");
+            if (pt != NO_PIECE_TYPE && move_promoted(move) != pt)
+                continue;
+            printf("move_in_movelist(%s%s) found from=%s to=%s\n",
+                   sq_to_string(from), sq_to_string(to),
+                   sq_to_string(move_from(move)),
+                   sq_to_string(move_to(move)));
+            return move;
+        } else
+            puts("");
+    }
+    return MOVE_NONE;
+}
+
+static move_t move_from_str(pos_t *pos, const char *move)
+{
+    movelist_t movelist;
+    square_t from = sq_from_string(move);
+    square_t to = sq_from_string(move + 2);
+    piece_type_t promoted = piece_t_from_char(*(move + 4));
+    printf("from=%o to=%o promoted=%d\n", from, to, promoted);
+
+    pos_set_checkers_pinners_blockers(pos);
+    pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+    return  move_in_movelist(&movelist, from, to, promoted);
+}
+
+static void pr_entry(hentry_t *entry)
+{
+    if (!entry)
+        printf("entry: NULL\n");
+    else {
+        printf("entry: key=%lx depth=%d n=%lu\n",
+               entry->key, HASH_PERFT_DEPTH(entry->data),
+               HASH_PERFT_VAL(entry->data));
+    }
+}
+
+int main()
+{
+    pos_t *pos = NULL;
+    char *token, *str, buf[128];
+    hentry_t *entry;
+    move_t move;
+    state_t state;
+    //movelist_t movelist;
+
+    const char *moves_array[] = {
+        "e2e4 e7e5 g1f3 b8c6",
+        "e2e4 b8c6 g1f3 e7e5"
+    };
+
+    init_all();
+
+    for (uint i = 0; i < ARRAY_SIZE(moves_array); ++i) {
+        int depth = 0;
+        str = strdup(moves_array[i]);
+        printf("%2d: ", i + 1);
+
+        pos = startpos(pos);
+        entry = tt_store_perft(pos->key, 0, 123 + depth);
+        pr_entry(entry);
+        token = strtok(str, " \t");
+        while (token) {
+            depth++;
+            printf("%s ", token);
+
+            //pos_set_checkers_pinners_blockers(pos);
+            //pos_legal(pos, pos_gen_pseudo(pos, &movelist));
+            move = move_from_str(pos, token);
+            printf("move: %s\n", move_to_str(buf, move, 0));
+            move_do(pos, move, &state);
+            if ((entry = tt_probe_perft(pos->key, depth))) {
+                printf("tt hit: depth=%d val=%lu",
+                       HASH_PERFT_DEPTH(entry->data),
+                       HASH_PERFT_VAL(entry->data));
+            } else {
+                tt_store_perft(pos->key, i + 1, depth);
+                printf("tt store: depth=%d val=%lu", depth, (u64)i * 123);
+            };
+
+            token = strtok(NULL, " \t");
+        }
+        printf("\n");
+        free(str);
+    }
+    return 0;
+}
+
+/* ccls bug report: https://github.com/emacs-lsp/emacs-ccls/issues/126
+ */
+/*
+ * int called(int), caller();
+ *
+ * /\**
+ *  * called() - test ccls.
+ *  * @x: int, the test value
+ *  *
+ *  * @called() description.
+ *  *
+ *  * @return: int, a very interesting value.
+ *  *\/
+ * int called(int x) { return x; }
+ *
+ * int caller()
+ * {
+ *     int i = 0;
+ *     called(int x)
+ *     return i;
+ * }
+ */