misc unfinished changes (kinda stash)

src/eval-simple.c

@@ -48,19 +48,15 @@ eval_t eval_material(pos_t *pos)
  * eval_simple() - simple and fast position evaluation
  * @pos: &position to evaluate
  *
- * This function is normally used only during initialization,
- * or when changing phase (middlegame <--> endgame), as the eval
- * will be done incrementally when doing moves.
- *
  * @return: the @pos evaluation in centipawns
  */
 eval_t eval_simple(pos_t *pos)
 {
-    eval_t eval[2] = { 0, 0 };
+    eval_t eval[2] = { 0, 0 }, res;
     eval_t mg_eval[2], eg_eval[2];
-    //struct pc_sq = sq_ int (*gg)[6 + 2][64] = eg? pc_sq_eg: pc_sq_mg;
 
-    //pos->eval_simple_phase = ENDGAME;
+    int eg_weight = clamp((int) pos->phase, ALL_PHASE, 0);
+    int mg_weight = ALL_PHASE - pos->phase;
 
     for (color_t color = WHITE; color < COLOR_NB; ++color) {
         mg_eval[color] = 0;
@@ -80,10 +76,15 @@ eval_t eval_simple(pos_t *pos)
 
         }
     }
+    eval[WHITE] = mg_eval[WHITE] * mg_weight + eg_eval[WHITE] * eg_weight;
+    eval[BLACK] = mg_eval[BLACK] * mg_weight + eg_eval[BLACK] * eg_weight;
+    res = (eval[WHITE] - eval[BLACK]) / ALL_PHASE;
 #   ifdef DEBUG_EVAL
-    printf("phase:%d mg[WHITE]:%d mg[BLACK]:%d eg[WHITE]:%d eg[BLACK]:%d\n",
+    printf("phase:%d mg:%d/%d eg:%d/%d ev:%d/%d RES=%d\n",
-           pos->phase, mg_eval[WHITE], mg_eval[BLACK], eg_eval[WHITE], eg_eval[BLACK]);
+           pos->phase, mg_eval[WHITE], mg_eval[BLACK],
+           eg_eval[WHITE], eg_eval[BLACK],
+           eval[WHITE], eval[BLACK], res
+        );
 #   endif
-
+    return res;
-    return eval[WHITE] - eval[BLACK];
 }

src/hash.h

@@ -44,14 +44,16 @@ typedef u64 hkey_t;                               /* cannot use typedef for key_
  * 16 bytes in future, it should be updated to be exactly 32 bytes.
  */
 typedef struct {
-    hkey_t key;                                   /* zobrist */
+    hkey_t key;                                   /* position key */
     union {
         u64 data;
         struct {
-            u16 depth;                            /* ply in search */
+            s16 eval;                             /* 16: eval */
-            s16 eval;
+            move_t move;                          /* 16: best move */
-            move_t move;
+            u8 depth;                             /*  8: search depth */
-            //u8 flags;                             /* maybe for locking, etc... */
+            u8 gen8;                              /*  8: search generation */
+
+            //flags;                             /* maybe for locking, etc... */
             //u8 filler;
         };
     };

src/search.c

@@ -15,6 +15,8 @@
 
 #include <brlib.h>
 
+#include "chessdefs.h"
+
 #include "position.h"
 #include "move-gen.h"
 #include "move-do.h"
@@ -22,6 +24,8 @@
 #include "attack.h"
 #include "hist.h"
 
+search_uci_t search_uci;
+
 /**
  * is_draw() - check if position is draw by 50 or repetition rule.
  * @pos: &position to search
@@ -55,20 +59,25 @@ eval_t negamax(pos_t *pos, int depth, int color)
     movelist_t movelist;
 
     pos->node_count++;
+
+    if (pos_repcount(pos))                        /* repetition */
+        return EVAL_DRAW * color;
+
+    pos_set_checkers_pinners_blockers(pos);
+    pos_gen_legal(pos, &movelist);
+
+    if (!movelist.nmoves)                         /* no move: mate ot draw */
+        return (pos->checkers? EVAL_MATE: EVAL_DRAW) * color;
+
     if (depth == 0) {
         score = eval(pos) * color;
         return score;
     }
-    pos_set_checkers_pinners_blockers(pos);
+
-    pos_gen_legal(pos, &movelist);
     last = movelist.move + movelist.nmoves;
-    //moves_gen_all(pos);
     for (move = movelist.move; move < last; ++move) {
-        //list_for_each_entry(move, &pos->moves[pos->turn], list) {
         move_do(pos, *move, &state);
         score = -negamax(pos, depth - 1, -color);
-        pos->node_count += pos->node_count;
-        //move->negamax = score;
         if (score > best) {
             best = score;
             pos->eval = best;
@@ -78,6 +87,21 @@ eval_t negamax(pos_t *pos, int depth, int color)
     return best;
 }
 
+/**
+ * search() - do (iterative) search.
+ * @pos: &position to search
+ * @depth: wanted depth.
+ * @alpha: alpha.
+ * @beta: beta.
+ * @color: 1 for white, -1 for black.
+ *
+ *
+ * @return: The @pos PVS evaluation.
+ */
+void search(__unused pos_t *pos)
+{
+
+}
 
 /**
  * pvs() - Principal Variation Search.

src/search.h

@@ -16,8 +16,21 @@
 
 #include "position.h"
 
+/**
+ * search_values_t - search values given by "go" command
+ * @depth: max depth "go depth X", MAX_DEPTH for no limit
+ *
+ *
+ */
+typedef struct {
+    u16 depth;                                    /* go depth X */
+} search_uci_t;
+
+extern search_uci_t search_uci;
+
 bool is_draw(pos_t *pos);
-//eval_t negamax(pos_t *pos, int depth, int color);
+eval_t negamax(pos_t *pos, int depth, int color);
+void search(pos_t *pos);
 //eval_t pvs(pos_t *pos, int depth, int alpha, int beta, int color);
 
 #endif  /* SEARCH_H */

src/uci.c

@@ -17,6 +17,7 @@
 #include <ctype.h>
 
 #include <brlib.h>
+#include <bug.h>
 
 #include "chessdefs.h"
 #include "util.h"
@@ -50,6 +51,7 @@ int do_quit(pos_t *, char *);
 
 int do_setoption(pos_t *, char *);
 int do_position(pos_t *, char *);
+int do_go(pos_t *, char *);
 
 /* commands *NOT* in UCI standard */
 int do_moves(pos_t *, char *);
@@ -66,6 +68,8 @@ struct command commands[] = {
     { "isready",    do_isready, "" },
     { "setoption",  do_setoption, ""},
     { "position",   do_position, "position startpos|fen [moves ...]" },
+    { "go",         do_go, "go" },
+
 
     { "perft",      do_perft, "(not UCI) perft [divide] [alt] depth" },
     { "moves",      do_moves, "(not UCI) moves ..." },
@@ -334,13 +338,12 @@ int do_setoption(__unused pos_t *pos, __unused char *arg)
 
 int do_position(pos_t *pos, char *arg)
 {
-    char *saveptr, *token, *fen, *moves;
+    char *saveptr = NULL, *token, *fen, *moves;
 
     hist_init();
 
     /* separate "moves" section */
     moves = str_token(arg, "moves");
-    saveptr = NULL;
     token = strtok_r(arg, " ", &saveptr);
     if (!strcmp(token, "startpos")) {
         startpos(pos);
@@ -374,13 +377,56 @@ int do_position(pos_t *pos, char *arg)
     return 1;
 }
 
+
+int do_go(pos_t *pos, char *arg)
+{
+    char *ptr = NULL, *tok, *val;
+
+    //token = strtok_r(arg, " ", &saveptr);
+    for (tok = strtok_r(arg, " ", &ptr); tok; tok = strtok_r(arg, " ", &ptr)) {
+        /* TODO: Find a "clever" way to get the different values without
+         * multiple "strcmp"
+         */
+
+        if (!strcmp(tok, "searchmoves")) {        /* moves list */
+            ;
+        } else if (!strcmp(tok, "wtime")) {       /* integer */
+            ;
+        } else if (!strcmp(tok, "btime")) {       /* integer */
+            ;
+        } else if (!strcmp(tok, "winc")) {        /* integer */
+            ;
+        } else if (!strcmp(tok, "binc")) {        /* integer */
+            ;
+        } else if (!strcmp(tok, "movestogo")) {   /* integer */
+            ;
+        } else if (!strcmp(tok, "depth")) {       /* integer */
+            if ((val = strtok_r(arg, " ", &ptr)))
+                search_uci.depth = atoi(val);
+            ;
+        } else if (!strcmp(tok, "nodes")) {       /* integer */
+            ;
+        } else if (!strcmp(tok, "mate")) {        /* integer */
+            ;
+        } else if (!strcmp(tok, "movetime")) {    /* integer */
+            ;
+        } else if (!strcmp(tok, "ponder")) {      /* no param */
+            ;
+        } else if (!strcmp(tok, "infinite")) {    /* no param */
+            ;
+        }
+
+    }
+    search(pos);
+    return 1;
+}
+
 int do_moves(__unused pos_t *pos, char *arg)
 {
     char *saveptr = NULL, *token, check[8];
     move_t move;
     movelist_t movelist;
 
-    saveptr = NULL;
     token = strtok_r(arg, " ", &saveptr);
     while (token) {
         move = move_from_str(token);