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- /*
- * util.c - C source for GNU CHESS
- *
- * Copyright (c) 1988,1989,1990 John Stanback
- * Copyright (c) 1992 Free Software Foundation
- *
- * This file is part of GNU CHESS.
- *
- * GNU Chess is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2, or (at your option)
- * any later version.
- *
- * GNU Chess is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with GNU Chess; see the file COPYING. If not, write to
- * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
- */
- #include "gnuchess.h"
- unsigned int TTadd = 0;
- short int recycle;
- short int ISZERO = 1;
- extern char mvstr[4][6];
- #ifdef CACHE
- extern struct etable __far etab[2][ETABLE];
- #endif
-
- int
- parse (FILE * fd, short unsigned int *mv, short int side, char *opening)
- {
- register int c, i, r1, r2, c1, c2;
- char s[128];
- char *p;
-
- while ((c = getc (fd)) == ' ' || c == '\n') ;
- i = 0;
- s[0] = (char) c;
- if (c == '!')
- {
- p = opening;
- do
- {
- *p++ = c;
- c = getc (fd);
- if (c == '\n' || c == EOF)
- {
- *p = '\0';
- return 0;
- }
- } while (true);
- }
- while (c != '?' && c != ' ' && c != '\t' && c != '\n' && c != EOF)
- s[++i] = (char) (c = getc (fd));
- s[++i] = '\0';
- if (c == EOF)
- return (-1);
- if (s[0] == '!' || s[0] == ';' || i < 3)
- {
- while (c != '\n' && c != EOF)
- c = getc (fd);
- return (0);
- }
- if (s[4] == 'o')
- *mv = ((side == black) ? LONGBLACKCASTLE : LONGWHITECASTLE);
- else if (s[0] == 'o')
- *mv = ((side == black) ? BLACKCASTLE : WHITECASTLE);
- else
- {
- c1 = s[0] - 'a';
- r1 = s[1] - '1';
- c2 = s[2] - 'a';
- r2 = s[3] - '1';
- *mv = (locn (r1, c1) << 8) | locn (r2, c2);
- }
- if (c == '?')
- { /* Bad move, not for the program to play */
- *mv |= 0x8000; /* Flag it ! */
- c = getc (fd);
- }
- return (1);
- }
-
-
- #if ttblsz
-
- #define CB(i) (unsigned char) ((color[2 * (i)] ? 0x80 : 0)\
- | (board[2 * (i)] << 4)\
- | (color[2 * (i) + 1] ? 0x8 : 0)\
- | (board[2 * (i) + 1]))
-
- int
- ProbeTTable (short int side,
- short int depth,
- short int ply,
- short int *alpha,
- short int *beta,
- short int *score)
-
- /*
- * Look for the current board position in the transposition table.
- */
-
- {
- register struct hashentry *ptbl;
- register /*unsigned*/ short i; /*to match new type of rehash --tpm*/
-
- ptbl = &ttable[side][hashkey & (ttblsize - 1)];
-
- /* rehash max rehash times */
- for (i = 0; (ptbl->depth) && (ptbl->hashbd != hashbd) && (i < rehash); i++) ptbl++;
- if ((ptbl->depth>= (short)depth) && (ptbl->hashbd == hashbd))
- /* ^^^^^^^^^^^^ we can use some informations of the entry even
- the depth is not large enough */
- {
- #ifdef HASHTEST
- for (i = 0; i < 32; i++)
- {
- if (ptbl->bd[i] != CB (i))
- {
- #ifndef BAREBONES
- HashCol++;
- ShowMessage (CP[199]); /*ttable collision detected*/
- #endif
- break;
- }
- }
- #endif /* HASHTEST */
-
-
- PV = SwagHt = ptbl->mv;
- if ((short) ptbl->depth >= depth)
- {
- #ifndef BAREBONES
- HashCnt++;
- #endif
- if (ptbl->flags & truescore)
- {
- *score = ptbl->score;
- /* adjust *score so moves to mate is from root */
- if (*score > 9000)
- *score -= ply;
- else if (*score < -9000)
- *score += ply;
- *beta = -20000;
- }
- #ifdef notdef /* Never happens! see search */
- else if (ptbl->flags & upperbound)
- {
- if (ptbl->score < *beta)
- *beta = ptbl->score + 1;
- }
- #endif
- else if (ptbl->flags & lowerbound)
- {
- if (ptbl->score > *alpha)
- *alpha = ptbl->score - 1;
- }
- return (true);
- }
- }
- return (false);
- }
-
-
- int
- PutInTTable (short int side,
- short int score,
- short int depth,
- short int ply,
- short int alpha,
- short int beta,
- short unsigned int mv)
-
- /*
- * Store the current board position in the transposition table.
- */
-
- {
- register struct hashentry *ptbl;
- register /*unsigned*/ short i; /*to match new type of rehash --tpm*/
-
- ptbl = &ttable[side][hashkey & (ttblsize - 1)];
-
- /* rehash max rehash times */
- for (i = 0; ptbl->depth && ptbl->hashbd != hashbd && i < rehash; i++)
- ptbl++;
- if (i == rehash) {
- #ifndef BAREBONES
- THashCol++;
- #endif
- ptbl += recycle;}
- if (depth >= (short)ptbl->depth || ptbl->hashbd != hashbd)
- {
- #ifndef BAREBONES
- TTadd++;
- HashAdd++;
- #endif
- ptbl->hashbd = hashbd;
- ptbl->depth = (unsigned char) depth;
- /* adjust score so moves to mate is from this ply */
- if (score > 9000)
- score += ply;
- else if (score < -9000)
- score -= ply;
- ptbl->score = score;
- ptbl->mv = mv;
- #ifdef DEBUG4
- if (debuglevel & 32)
- {
- algbr (mv >> 8, mv & 0xff, 0);
- printf ("-add-> d=%d s=%d p=%d a=%d b=%d %s\n", depth, score, ply, alpha, beta, mvstr);
- }
- #endif
- /*#ifdef notdef
- if (score < alpha)
- ptbl->flags = upperbound;
- else
- /*#endif /* 0 */
- if (score > beta)
- {
- ptbl->flags = lowerbound;
- ptbl->score = beta + 1;
- }
- else
- ptbl->flags = truescore;
-
- #ifdef HASHTEST
- for (i = 0; i < 32; i++)
- {
- ptbl->bd[i] = CB (i);
- }
- #endif /* HASHTEST */
- return true;
- }
- return false;
- }
-
-
- static struct hashentry *ttagew, *ttageb;
-
- void
- ZeroTTable (void)
- {
- register struct hashentry *w, *b;
-
- /* I am adding these 2 memsets! */
- memset((char *)ttable[0],0,sizeof(struct hashentry)*(ttblsize+rehash));
- memset((char *)ttable[1],0,sizeof(struct hashentry)*(ttblsize+rehash));
- for(w=ttable[white],b=ttable[black];w<&ttable[white][ttblsize];w++,b++)
- { w->depth = 0; b->depth = 0;}
- ttagew = ttable[white]; ttageb = ttable[black];
- #ifdef CACHE
- memset ((char *) etab, 0, sizeof (etab));
- #endif
- #ifdef notdef
- register unsigned int a;
- for (a = 0; a < ttblsize + (unsigned int)rehash; a++)
- {
- ttable[white][a].depth = 0;
- ttable[black][a].depth = 0;
- }
- #endif
- TTadd = 0;
- }
-
- #ifdef HASHFILE
- int Fbdcmp(char *a,char *b)
- {
- register int i;
- for(i = 0;i<32;i++)
- if(a[i] != b[i])return false;
- return true;
- }
- int
- ProbeFTable (short int side,
- short int depth,
- short int ply,
- short int *alpha,
- short int *beta,
- short int *score)
-
- /*
- * Look for the current board position in the persistent transposition table.
- */
-
- {
- register short int i;
- register unsigned long hashix;
- struct fileentry new, t;
-
- hashix = ((side == white) ? (hashkey & 0xFFFFFFFE) : (hashkey | 1)) & filesz;
-
- for (i = 0; i < 32; i++)
- new.bd[i] = CB (i);
- new.flags = 0;
- if (Mvboard[kingP[side]] == 0)
- {
- if (Mvboard[qrook[side]] == 0)
- new.flags |= queencastle;
- if (Mvboard[krook[side]] == 0)
- new.flags |= kingcastle;
- }
- for (i = 0; i < frehash; i++)
- {
- fseek (hashfile,
- sizeof (struct fileentry) * ((hashix + 2 * i) & (filesz)),
- SEEK_SET);
- fread (&t, sizeof (struct fileentry), 1, hashfile);
- if (!t.depth) break;
- if(!Fbdcmp(t.bd, new.bd)) continue;
- if (((short int) t.depth >= depth)
- && (new.flags == (unsigned short)(t.flags & (kingcastle | queencastle))))
- {
- #ifndef BAREBONES
- FHashCnt++;
- #endif
- PV = (t.f << 8) | t.t;
- *score = (t.sh << 8) | t.sl;
- /* adjust *score so moves to mate is from root */
- if (*score > 9000)
- *score -= ply;
- else if (*score < -9000)
- *score += ply;
- if (t.flags & truescore)
- {
- *beta = -20000;
- }
- else if (t.flags & lowerbound)
- {
- if (*score > *alpha)
- *alpha = *score - 1;
- }
- else if (t.flags & upperbound)
- {
- if (*score < *beta)
- *beta = *score + 1;
- }
- return (true);
- }
- }
- return (false);
- }
-
- void
- PutInFTable (short int side,
- short int score,
- short int depth,
- short int ply,
- short int alpha,
- short int beta,
- short unsigned int f,
- short unsigned int t)
-
- /*
- * Store the current board position in the persistent transposition table.
- */
-
- {
- register unsigned short i;
- register unsigned long hashix;
- struct fileentry new, tmp;
-
- hashix = ((side == white) ? (hashkey & 0xFFFFFFFE) : (hashkey | 1)) & filesz;
- for (i = 0; i < 32; i++) new.bd[i] = CB (i);
- new.f = (unsigned char) f;
- new.t = (unsigned char) t;
- if (score < alpha)
- new.flags = upperbound;
- else
- new.flags = ((score > beta) ? lowerbound : truescore);
- if (Mvboard[kingP[side]] == 0)
- {
- if (Mvboard[qrook[side]] == 0)
- new.flags |= queencastle;
- if (Mvboard[krook[side]] == 0)
- new.flags |= kingcastle;
- }
- new.depth = (unsigned char) depth;
- /* adjust *score so moves to mate is from root */
- if (score > 9000)
- score += ply;
- else if (score < -9000)
- score -= ply;
-
-
- new.sh = (unsigned char) (score >> 8);
- new.sl = (unsigned char) (score & 0xFF);
-
- for (i = 0; i < frehash; i++)
- {
- fseek (hashfile,
- sizeof (struct fileentry) * ((hashix + 2 * i) & (filesz)),
- SEEK_SET);
- if(fread (&tmp, sizeof (struct fileentry), 1, hashfile) == NULL){perror("hashfile");exit(1);}
- if (tmp.depth && !Fbdcmp(tmp.bd,new.bd))continue;
- if(tmp.depth == depth)break;
- if (!tmp.depth || (short) tmp.depth < depth)
- {
- fseek (hashfile,
- sizeof (struct fileentry) * ((hashix + 2 * i) & (filesz)),
- SEEK_SET);
- fwrite (&new, sizeof (struct fileentry), 1, hashfile);
- #ifndef BAREBONES
- FHashAdd++;
- #endif
- break;
- }
- }
- }
-
- #endif /* HASHFILE */
- #endif /* ttblsz */
-
- void
- ZeroRPT (void)
- {
- #ifdef NOMEMSET
- register int side, i;
- for (side = white; side <= black; side++)
- for (i = 0; i < 256;)
- rpthash[side][i++] = 0;
- #else
- if(ISZERO){memset ((char *) rpthash, 0, sizeof (rpthash));ISZERO=0;}
- #endif
- }
-