Example #1
0
/*-------------------------------------------------------------------------*
 * EXISTENTIAL_VARIABLES                                                   *
 *                                                                         *
 *-------------------------------------------------------------------------*/
static WamWord
Existential_Variables(WamWord start_word)
{
  WamWord word, tag_mask;
  WamWord *adr;

  DEREF(start_word, word, tag_mask);
  
  if (tag_mask == TAG_STC_MASK)
    {
      adr = UnTag_STC(word);
      if (Functor_And_Arity(adr) == exist_2)
	{
	  Pl_Treat_Vars_Of_Term(Arg(adr, 0), TRUE, Bound_Var);
	  word = Existential_Variables(Arg(adr, 1));
	}
    }

  return word;
}
Example #2
0
/*-------------------------------------------------------------------------*
 * SHOW_STRUCTURE                                                          *
 *                                                                         *
 *-------------------------------------------------------------------------*/
static void
Show_Structure(int depth, int prec, int context, WamWord *stc_adr)
{
  WamWord word, tag_mask;
  WamWord *adr;
  WamWord f_n = Functor_And_Arity(stc_adr);
  int functor = Functor(stc_adr);
  int arity = Arity(stc_adr);
  OperInf *oper;
  int nb_args_to_disp;
  int i, j, n;
  char str[32];
  Bool bracket;
  Bool surround_space;
  char *p;


  depth--;

  if (name_vars && f_n == dollar_varname_1 && stc_adr >= name_number_above_H)
    {
      DEREF(Arg(stc_adr, 0), word, tag_mask);
      if (tag_mask == TAG_ATM_MASK)
	{
	  p = pl_atom_tbl[UnTag_ATM(word)].name;
	  if (Is_Valid_Var_Name(p))
	    {
	      Out_String(p);
	      pl_last_writing = W_IDENTIFIER;
	      return;
	    }
	}
    }

  if (number_vars && f_n == dollar_var_1 && stc_adr >= name_number_above_H)
    {
      DEREF(Arg(stc_adr, 0), word, tag_mask);
      if (tag_mask == TAG_INT_MASK && (n = UnTag_INT(word)) >= 0)
	{
	  i = n % 26;
	  j = n / 26;

	  Out_Char('A' + i);

	  if (j)
	    {
	      sprintf(str, "%d", j);
	      Out_String(str);
	    }

	  pl_last_writing = W_IDENTIFIER;
	  return;
	}
    }

  if (ignore_op || arity > 2)
    goto functional;

  if (f_n == curly_brackets_1)
    {
      Out_Char('{');
      if (space_args)
	Out_Space();
      Show_Term(depth, MAX_PREC, GENERAL_TERM, Arg(stc_adr, 0));
      if (space_args)
	Out_Space();
      Out_Char('}');
      return;
    }

  bracket = FALSE;

  if (arity == 1 && (oper = Pl_Lookup_Oper(functor, PREFIX)))
    {
#if 1
      /* Koen de Bosschere says "in case of ambiguity :          */
      /* select the associative operator over the nonassociative */
      /* select prefix over postfix".                            */

      OperInf *oper1;

      if (oper->prec > oper->right
	  && (oper1 = Pl_Lookup_Oper(functor, POSTFIX))
	  && oper1->left == oper1->prec)
	{
	  oper = oper1;
	  goto postfix;
	}
#endif
      if (oper->prec > prec || (context == INSIDE_LEFT_ASSOC_OP &&
				(oper->prec == oper->right
				 && oper->prec == prec)))
	{			/* prevent also the case: fy T yf(x) */
	  Out_Char('(');
	  bracket = TRUE;
	}


      Show_Atom(GENERAL_TERM, functor);

      last_prefix_op = W_PREFIX_OP_ANY;

      if (space_args
#if SPACE_ARGS_RESTRICTED	/* space_args -> space after fx operator */
	  && oper->prec > oper->right
#endif
	  )
	Out_Space();
      else
	if (strcmp(pl_atom_tbl[functor].name, "-") == 0)
	  {
	    last_prefix_op = W_PREFIX_OP_MINUS;
	    p_bracket_minus = &bracket;
	  }

      Show_Term(depth, oper->right, INSIDE_ANY_OP, Arg(stc_adr, 0));
      last_prefix_op = W_NO_PREFIX_OP;

      /* Here we need a while(bracket--) instead of if(bracket) because
       * in some cases with the minus op and additional bracket is needed.
       * Example: with op(100, xfx, &) (recall the prec of - is 200). 
       * The term ((-(1)) & b must be displayed as: (- (1)) & b
       * Concerning the sub-term - (1), the first ( is emitted  10 lines above
       * because the precedence of - (200) is > precedence of & (100).
       * The second ( is emitted by Need_Space() because the argument of - begins 
       * by a digit. At the return we have to close 2 ).
       */

      while (bracket--)	
	Out_Char(')');

      return;
    }


  if (arity == 1 && (oper = Pl_Lookup_Oper(functor, POSTFIX)))
    {
    postfix:
      if (oper->prec > prec)
	{
	  Out_Char('(');
	  bracket = TRUE;
	}

      context =
	(oper->left == oper->prec) ? INSIDE_LEFT_ASSOC_OP : INSIDE_ANY_OP;

      Show_Term(depth, oper->left, context, Arg(stc_adr, 0));

      if (space_args
#if SPACE_ARGS_RESTRICTED	/* space_args -> space before xf operator */
	  && oper->prec > oper->left
#endif
	  )
	Out_Space();

      Show_Atom(GENERAL_TERM, functor);

      if (bracket)
	Out_Char(')');

      return;
    }


  if (arity == 2 && (oper = Pl_Lookup_Oper(functor, INFIX)))
    {
      if (oper->prec > prec || (context == INSIDE_LEFT_ASSOC_OP &&
				(oper->prec == oper->right
				 && oper->prec == prec)))
	{			/* prevent also the case: T xfy U yf(x) */
	  Out_Char('(');
	  bracket = TRUE;
	}

      context =
	(oper->left == oper->prec) ? INSIDE_LEFT_ASSOC_OP : INSIDE_ANY_OP;

      Show_Term(depth, oper->left, context, Arg(stc_adr, 0));

#if 1 /* to show | unquoted if it is an infix operator with prec > 1000 */
      if (functor == ATOM_CHAR('|') && oper->prec > 1000)
	{
	  if (space_args)
	    Out_Space();
	  Out_Char('|');
	  if (space_args)
	    Out_Space();
	}
      else
#endif
	if (functor == ATOM_CHAR(','))
	  {
	    Out_Char(',');
	    if (space_args)
	      Out_Space();
	  }
	else
	  {
	    surround_space = FALSE;

	    if (pl_atom_tbl[functor].prop.type == IDENTIFIER_ATOM ||
		pl_atom_tbl[functor].prop.type == OTHER_ATOM ||
		(space_args
#ifdef SPACE_ARGS_RESTRICTED	/* space_args -> space around xfx operators */
		 && oper->left != oper->prec && oper->right != oper->prec
#endif
		 ))
	      {
		surround_space = TRUE;
		Out_Space();
	      }

	    Show_Atom(GENERAL_TERM, functor);

	    if (surround_space)
	      Out_Space();
	  }

      Show_Term(depth, oper->right, INSIDE_ANY_OP, Arg(stc_adr, 1));

      if (bracket)
	Out_Char(')');

      return;
    }



 functional:			/* functional notation */

  Show_Atom(GENERAL_TERM, functor);
  Out_Char('(');

  nb_args_to_disp = i = (arity < depth + 1 || depth < 0) ? arity : depth + 1;
  adr = &Arg(stc_adr, 0);

  goto start_display;

  do
    {
      Out_Char(',');
      if (space_args)
	Out_Space();
    start_display:
      Show_Term(depth, MAX_ARG_OF_FUNCTOR_PREC, GENERAL_TERM, *adr++);
    }
  while (--i);

  if (arity != nb_args_to_disp)
    {
      Out_Char(',');
      if (space_args)
	Out_Space();
      Show_Atom(GENERAL_TERM, atom_dots);
    }

  Out_Char(')');
}
Example #3
0
/*-------------------------------------------------------------------------*
 * LOAD_MATH_EXPRESSION                                                    *
 *                                                                         *
 *-------------------------------------------------------------------------*/
static WamWord
Load_Math_Expression(WamWord exp)
{
  WamWord word, tag_mask;
  WamWord *adr;
  WamWord *lst_adr;
  ArithInf *arith;

  DEREF(exp, word, tag_mask);

  if (tag_mask == TAG_INT_MASK || tag_mask == TAG_FLT_MASK)
    return word;

  if (tag_mask == TAG_LST_MASK)
    {
      lst_adr = UnTag_LST(word);
      DEREF(Cdr(lst_adr), word, tag_mask);
      if (word != NIL_WORD)
	{
	  word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
	  Pl_Unify_Atom(ATOM_CHAR('.'));
	  Pl_Unify_Integer(2);
	  Pl_Err_Type(pl_type_evaluable, word);
	}
      DEREF(Car(lst_adr), word, tag_mask);
      if (tag_mask == TAG_REF_MASK)
	Pl_Err_Instantiation();

      if (tag_mask != TAG_INT_MASK) 
	{
	  Pl_Err_Type(pl_type_integer, word);
	}
      return word;
    }

  if (tag_mask == TAG_STC_MASK)
    {
      adr = UnTag_STC(word);

      arith = (ArithInf *) Pl_Hash_Find(arith_tbl, Functor_And_Arity(adr));
      if (arith == NULL)
	{
	  word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
	  Pl_Unify_Atom(Functor(adr));
	  Pl_Unify_Integer(Arity(adr));
	  Pl_Err_Type(pl_type_evaluable, word);
	}
      
      if (Arity(adr) == 1)
	return (*(arith->fct)) (Load_Math_Expression(Arg(adr, 0)));

      return (*(arith->fct)) (Load_Math_Expression(Arg(adr, 0)),
			      Load_Math_Expression(Arg(adr, 1)));
    }

  if (tag_mask == TAG_REF_MASK)
    Pl_Err_Instantiation();

  if (tag_mask == TAG_ATM_MASK)
    {
      word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
      Pl_Unify_Value(exp);
      Pl_Unify_Integer(0);		/* then type_error */
    }

  Pl_Err_Type(pl_type_evaluable, word);
  return word;
}
Example #4
0
/*-------------------------------------------------------------------------*
 * SIMPLIFY                                                                *
 *                                                                         *
 * This function returns the result of the simplified boolean expression   *
 * given in e_word. NOT operators are only applied to variables.           *
 *                                                                         *
 * Input:                                                                  *
 *    sign  : current sign of the boolean term (-1 (inside a ~) or +1)     *
 *    e_word: boolean term to simplify                                     *
 *                                                                         *
 * Output:                                                                 *
 *    The returned result is a pointer to a node of the following form:    *
 *                                                                         *
 *    for binary boolean not operator (~):                                 *
 *        [1]: variable involved (tagged word)                             *
 *        [0]: operator NOT                                                *
 *                                                                         *
 *    for unary boolean operators (<=> ~<=> ==> ~==> /\ ~/\ \/ ~\/):       *
 *        [2]: right boolean exp (pointer to node)                         *
 *        [1]: left  boolean exp (pointer to node)                         *
 *        [0]: operator (EQUIV, NEQUIV, IMPLY, NIMPLY, AND, NAND, OR, NOR) *
 *                                                                         *
 *    for boolean false value (0):                                         *
 *        [0]: ZERO                                                        *
 *                                                                         *
 *    for boolean true value (1):                                          *
 *        [0]: ONE                                                         *
 *                                                                         *
 *    for boolean variable:                                                *
 *        [0]: tagged word                                                 *
 *                                                                         *
 *    for binary math operators (= \= < >= > <=) (partial / full AC):      *
 *        [2]: right math exp (tagged word)                                *
 *        [1]: left  math exp (tagged word)                                *
 *        [0]: operator (EQ, NEQ, LT, LTE, EQ_F, NEQ_F, LT_F, LTE_F)       *
 *             (GT, GTE, GT_F, and GTE_F becomes LT, LTE, LT_F and LTE_F)  *
 *                                                                         *
 * These nodes are stored in a hybrid stack. NB: XOR same as NEQUIV        *
 *-------------------------------------------------------------------------*/
static WamWord *
Simplify(int sign, WamWord e_word)
{
  WamWord word, tag_mask;
  WamWord *adr;
  WamWord f_n, le_word, re_word;
  int op, n;
  WamWord *exp, *sp1;
  WamWord l, r;

#ifdef DEBUG
  printf("ENTERING %5ld: %2d: ", sp - stack, sign);
  Pl_Write(e_word);
  printf("\n");
#endif

  exp = sp;

  if (sp - stack > BOOL_STACK_SIZE - 5)
    Pl_Err_Resource(pl_resource_too_big_fd_constraint);

  DEREF(e_word, word, tag_mask);
  if (tag_mask == TAG_REF_MASK || tag_mask == TAG_FDV_MASK)
    {
      adr = UnTag_Address(word);
      if (vars_sp - vars_tbl == VARS_STACK_SIZE)
	Pl_Err_Resource(pl_resource_too_big_fd_constraint);

      *vars_sp++ = word;
      *vars_sp++ = 0;		/* bool var */

      if (sign != 1)
	*sp++ = NOT;

      *sp++ = Tag_REF(adr);
      return exp;
    }

  if (tag_mask == TAG_INT_MASK)
    {
      n = UnTag_INT(word);
      if ((unsigned) n > 1)
	goto type_error;

      *sp++ = ZERO + ((sign == 1) ? n : 1 - n);
      return exp;
    }

  if (tag_mask == TAG_ATM_MASK)
    {
      word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
      Pl_Unify_Value(e_word);
      Pl_Unify_Integer(0);
    type_error:
      Pl_Err_Type(pl_type_fd_bool_evaluable, word);
    }


  if (tag_mask != TAG_STC_MASK)
    goto type_error;

  adr = UnTag_STC(word);

  f_n = Functor_And_Arity(adr);
  if (bool_xor == f_n)
    op = NEQUIV;
  else
    {
      for (op = 0; op < NB_OF_OP; op++)
	if (bool_tbl[op] == f_n)
	  break;

      if (op == NB_OF_OP)
	{
	  word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
	  Pl_Unify_Atom(Functor(adr));
	  Pl_Unify_Integer(Arity(adr));
	  goto type_error;
	}
    }

  le_word = Arg(adr, 0);
  re_word = Arg(adr, 1);

  if (op == NOT)
    return Simplify(-sign, le_word);

  if (sign != 1)
    op = (op % 2 == EQ % 2) ? op + 1 : op - 1;

  if (op >= EQ && op <= LTE_F)
    {
      Add_Fd_Variables(le_word);
      Add_Fd_Variables(re_word);

      n = (op == GT || op == GT_F) ? op - 2 :
	(op == GTE || op == GTE_F) ? op + 2 : op;

      *sp++ = n;
      *sp++ = (n == op) ? le_word : re_word;
      *sp++ = (n == op) ? re_word : le_word;
      return exp;
    }

  sp += 3;
  exp[0] = op;
  exp[1] = (WamWord) Simplify(1, le_word);
  sp1 = sp;
  exp[2] = (WamWord) Simplify(1, re_word);

  l = *(WamWord *) (exp[1]);
  r = *(WamWord *) (exp[2]);

  /* NB: beware when calling below Simplify() (while has been just called above)
   * this can ran into stack overflow (N^2 space complexity). 
   * Try to recover the stack before calling Simplify().
   * Other stack recovery are less important (e.g. when only using exp[1]).
   *
   * In the following exp[] += sizeof(WamWord) is used to "skip" the NOT
   * in a simplification (points to the next cell).
   */

  switch (op)
    {
    case EQUIV:
      if (l == ZERO)		/* 0 <=> R is ~R */
	{
	  sp = exp;
	  return Simplify(-1, re_word);
	}

      if (l == ONE)		/* 1 <=> R is R */
	{
	  return (WamWord *) exp[2];
	}

      if (r == ZERO)		/* L <=> 0 is ~L */
	{
	  sp = exp;
	  return Simplify(-1, le_word);
	}

      if (r == ONE)		/* L <=> 1 is L */
	{
	  sp = sp1;
	  return (WamWord *) exp[1];
	}

      if (l == NOT)		/* ~X <=> R is X <=> ~R */
	{
	  exp[1] += sizeof(WamWord); 
	  sp = sp1;
	  exp[2] = (WamWord) Simplify(-1, re_word);
	  break;
	}

      if (r == NOT)		/* L <=> ~X is ~L <=> X */
	{			/* NB: cannot recover the stack */	  
	  exp[1] = (WamWord) Simplify(-1, le_word);
	  exp[2] += sizeof(WamWord);
	  break;
	}
      break;

    case NEQUIV:
      if (l == ZERO)		/* 0 ~<=> R is R */
	{
	  return (WamWord *) exp[2];
	}

      if (l == ONE)		/* 1 ~<=> R is ~R */
	{
	  sp = exp;
	  return Simplify(-1, re_word);
	}

      if (r == ZERO)		/* L ~<=> 0 is L */
	{
	  sp = sp1;
	  return (WamWord *) exp[1];
	}

      if (r == ONE)		/* L ~<=> 1 is ~L */
	{
	  sp = exp;
	  return Simplify(-1, le_word);
	}

      if (l == NOT)		/* ~X ~<=> R is X <=> R */
	{
	  exp[0] = EQUIV;
	  exp[1] += sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L ~<=> ~X is L <=> X */
	{
	  exp[0] = EQUIV;
	  exp[2] += sizeof(WamWord);
	  break;
	}

      if (IsVar(l) && !IsVar(r)) /* X ~<=> R is X <=> ~R */
	{
	  exp[0] = EQUIV;
	  sp = sp1;
	  exp[2] = (WamWord) Simplify(-1, re_word);
	  break;
	}

      if (IsVar(r) && !IsVar(l)) /* L ~<=> X is L <=> ~X */
	{
	  exp[0] = EQUIV;	/* NB: cannot recover the stack */
	  exp[1] = (WamWord) Simplify(-1, le_word);
	  break;
	}
      break;

    case IMPLY:
      if (l == ZERO || r == ONE) /* 0 ==> R is 1 , L ==> 1 is 1 */
	{
	  sp = exp;
	  *sp++ = ONE;
	  break;
	}

      if (l == ONE)		/* 1 ==> R is R */
	{
	  return (WamWord *) exp[2];
	}

      if (r == ZERO)		/* L ==> 0 is ~L */
	return sp = exp, Simplify(-1, le_word);

      if (l == NOT)		/* ~X ==> R is X \/ R */
	{
	  exp[0] = OR;
	  exp[1] += sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L ==> ~X is X ==> ~L */
	{
	  exp[1] = exp[2] + sizeof(WamWord);
	  exp[2] = (WamWord) Simplify(-1, le_word);
	  break;
	}
      break;

    case NIMPLY:
      if (l == ZERO || r == ONE) /* 0 ~==> R is 0 , L ~==> 1 is 0 */
	{
	  sp = exp;
	  *sp++ = ZERO;
	  break;
	}

      if (l == ONE)		/* 1 ~==> R is ~R */
	{
	  sp = exp;
	  return Simplify(-1, re_word);
	}

      if (r == ZERO)		/* L ~==> 0 is L */
	{
	  sp = sp1;
	  return (WamWord *) exp[1];
	}

      if (l == NOT)		/* ~X ~==> R is X ~\/ R */
	{
	  exp[0] = NOR;
	  exp[1] += sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L ~==> ~X is L /\ X */
	{
	  exp[0] = AND;
	  exp[2] += sizeof(WamWord);
	  break;
	}
      break;

    case AND:
      if (l == ZERO || r == ZERO) /* 0 /\ R is 0 , L /\ 0 is 0 */
	{
	  sp = exp;
	  *sp++ = ZERO;
	  break;
	}

      if (l == ONE)		/* 1 /\ R is R */
	{
	  return (WamWord *) exp[2];
	}

      if (r == ONE)		/* L /\ 1 is L */
	{
	  sp = sp1;
	  return (WamWord *) exp[1];
	}

      if (l == NOT)		/* ~X /\ R is R ~==> X */
	{
	  exp[0] = NIMPLY;
	  word = exp[1];
	  exp[1] = exp[2];
	  exp[2] = word + sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L /\ ~X is L ~==> X */
	{
	  exp[0] = NIMPLY;
	  exp[2] += sizeof(WamWord);
	  break;
	}
      break;

    case NAND:
      if (l == ZERO || r == ZERO) /* 0 ~/\ R is 1 , L ~/\ 0 is 1 */
	{
	  sp = exp;
	  *sp++ = ONE;
	  break;
	}

      if (l == ONE)		/* 1 ~/\ R is ~R */
	{
	  sp = exp;
	  return Simplify(-1, re_word);
	}

      if (r == ONE)		/* L ~/\ 1 is ~L */
	{
	  sp = exp;
	  return Simplify(-1, le_word);
	}

      if (l == NOT)		/* ~X ~/\ R is R ==> X */
	{
	  exp[0] = IMPLY;
	  word = exp[1];
	  exp[1] = exp[2];
	  exp[2] = word + sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L ~/\ ~X is L ==> X */
	{
	  exp[0] = IMPLY;
	  exp[2] += sizeof(WamWord);
	  break;
	}
      break;

    case OR:
      if (l == ONE || r == ONE)	/* 1 \/ R is 1 , L \/ 1 is 1 */
	{
	  sp = exp;
	  *sp++ = ONE;
	  break;
	}

      if (l == ZERO)		/* 0 \/ R is R */
	{
	  return (WamWord *) exp[2];
	}

      if (r == ZERO)		/* L \/ 0 is L */
	{
	  sp = sp1;
	  return (WamWord *) exp[1];
	}

      if (l == NOT)		/* ~X \/ R is X ==> R */
	{
	  exp[0] = IMPLY;
	  exp[1] += sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L \/ ~X is X ==> L */
	{
	  exp[0] = IMPLY;
	  word = exp[1];
	  exp[1] = exp[2] + sizeof(WamWord);
	  exp[2] = word;
	  break;
	}
      break;

    case NOR:
      if (l == ONE || r == ONE)	/* 1 ~\/ R is 0 , L ~\/ 1 is 0 */
	{
	  sp = exp;
	  *sp++ = ZERO;
	  break;
	}

      if (l == ZERO)		/* 0 ~\/ R is ~R */
	{
	  sp = exp;
	  return Simplify(-1, re_word);
	}

      if (r == ZERO)		/* L ~\/ 0 is ~L */
	{
	  sp = exp;
	  return Simplify(-1, le_word);
	}

      if (l == NOT)		/* ~X ~\/ R is X ~==> R */
	{
	  exp[0] = NIMPLY;
	  exp[1] += sizeof(WamWord);
	  break;
	}

      if (r == NOT)		/* L ~\/ ~X is X ~==> L */
	{
	  exp[0] = NIMPLY;
	  word = exp[1];
	  exp[1] = exp[2] + sizeof(WamWord);
	  exp[2] = word;
	  break;
	}
      break;
    }

  return exp;
}
Example #5
0
/*-------------------------------------------------------------------------*
 * This file is not compiled separately but included twice by wam_inst.c:  *
 *    - to define the Unify function (classical unification).              *
 *    - to define the Unify_Occurs_Check function (+ occurs check).        *
 *-------------------------------------------------------------------------*/
Bool FC
UNIFY_FCT_NAME(WamWord start_u_word, WamWord start_v_word)
{
  WamWord u_word, u_tag_mask;
  WamWord v_word, v_tag_mask;
  WamWord *u_adr, *v_adr;
  int i;

 terminal_rec:

  DEREF(start_u_word, u_word, u_tag_mask);
  DEREF(start_v_word, v_word, v_tag_mask);

  if (u_tag_mask == TAG_REF_MASK)
    {
      u_adr = UnTag_REF(u_word);
      if (v_tag_mask == TAG_REF_MASK)
	{
	  v_adr = UnTag_REF(v_word);

	  if (u_adr > v_adr)
	    Bind_UV(u_adr, Tag_REF(v_adr));
	  else if (v_adr > u_adr)
	    Bind_UV(v_adr, Tag_REF(u_adr));
	}
      else
	{
#ifdef OCCURS_CHECK
	  if (!Is_A_Local_Adr(u_adr) &&	/* no binding from heap to local */
	      Check_If_Var_Occurs(u_adr, v_word))
	    return FALSE;
#endif
	  Do_Copy_Of_Word(v_tag_mask, v_word);
	  Bind_UV(u_adr, v_word);
	}

      return TRUE;
    }


  if (v_tag_mask == TAG_REF_MASK)
    {
      v_adr = UnTag_REF(v_word);

#ifdef OCCURS_CHECK
      if (!Is_A_Local_Adr(v_adr) &&	/* no binding from heap to local */
	  Check_If_Var_Occurs(v_adr, u_word))
	return FALSE;
#endif
      Do_Copy_Of_Word(u_tag_mask, u_word);
      Bind_UV(v_adr, u_word);

      return TRUE;
    }

  if (u_word == v_word)
    return TRUE;

  if (v_tag_mask == TAG_LST_MASK)
    {
      if (u_tag_mask != v_tag_mask)
	return FALSE;

      u_adr = UnTag_LST(u_word);
      v_adr = UnTag_LST(v_word);

      u_adr = &Car(u_adr);
      v_adr = &Car(v_adr);

      if (!UNIFY_FCT_NAME(*u_adr++, *v_adr++))
	return FALSE;

      start_u_word = *u_adr;
      start_v_word = *v_adr;
      goto terminal_rec;
    }

  if (v_tag_mask == TAG_STC_MASK)
    {
      if (u_tag_mask != v_tag_mask)
	return FALSE;

      u_adr = UnTag_STC(u_word);
      v_adr = UnTag_STC(v_word);

      if (Functor_And_Arity(u_adr) != Functor_And_Arity(v_adr))
	return FALSE;

      i = Arity(u_adr);
      u_adr = &Arg(u_adr, 0);
      v_adr = &Arg(v_adr, 0);
      while (--i)
	if (!UNIFY_FCT_NAME(*u_adr++, *v_adr++))
	  return FALSE;

      start_u_word = *u_adr;
      start_v_word = *v_adr;
      goto terminal_rec;
    }

#ifndef NO_USE_FD_SOLVER
  if (v_tag_mask == TAG_INT_MASK && u_tag_mask == TAG_FDV_MASK)
    return Fd_Unify_With_Integer(UnTag_FDV(u_word), UnTag_INT(v_word));
     
  if (v_tag_mask == TAG_FDV_MASK)
    {
      v_adr = UnTag_FDV(v_word);

      if (u_tag_mask == TAG_INT_MASK)
	return Fd_Unify_With_Integer(v_adr, UnTag_INT(u_word));

      if (u_tag_mask != v_tag_mask) /* i.e. TAG_FDV_MASK */
	return FALSE;
      
      return Fd_Unify_With_Fd_Var(UnTag_FDV(u_word), v_adr);
    }
#endif

  if (v_tag_mask == TAG_FLT_MASK)
    return (u_tag_mask == v_tag_mask && 
	    Pl_Obtain_Float(UnTag_FLT(u_word)) ==
	    Pl_Obtain_Float(UnTag_FLT(v_word)));

  return FALSE;
}
Example #6
0
/*-------------------------------------------------------------------------*
 * NORMALIZE                                                               *
 *                                                                         *
 * This functions normalizes a term.                                       *
 * Input:                                                                  *
 *    e_word: term to normalize                                            *
 *    sign  : current sign of the term (-1 or +1)                          *
 *                                                                         *
 * Output:                                                                 *
 *    p     : the associated polynomial term                               *
 *                                                                         *
 * Normalizes the term and loads it into p.                                *
 * Non-Linear operations are simplified and loaded into a stack to be      *
 * executed later.                                                         *
 *                                                                         *
 * T1*T2 : T1 and T2 are normalized to give the polynomials p1 and p2, with*
 *         p1 = c1 + a1X1 + a2X2 + ... + anXn                              *
 *         p2 = c2 + b1X1 + b2X2 + ... + bmXm                              *
 *         and replaced by c1*c2 +                                         *
 *                         a1X1 * c2 + a1X1 * b1X1 + ... + a1X1 * bmXm     *
 *                         ...                                             *
 *                         anX1 * c2 + anXn * b1X1 + ... + anXn * bmXm     *
 *                                                                         *
 * T1**T2: T1 and T2 are loaded into 2 new words word1 and word2 that can  *
 *         be integers or variables (tagged words). The code emitted       *
 *         depends on 3 possibilities (var**var is not allowed)            *
 *         (+ optim 1**T2, 0**T2, T1**0, T1**1), NB 0**0=1                 *
 *-------------------------------------------------------------------------*/
static Bool
Normalize(WamWord e_word, int sign, Poly *p)
{
  WamWord word, tag_mask;
  WamWord *adr;
  WamWord *fdv_adr;
  WamWord word1, word2, word3;
  WamWord f_n, le_word, re_word;
  int i;
  PlLong n1, n2, n3;

 terminal_rec:

  DEREF(e_word, word, tag_mask);

  if (tag_mask == TAG_FDV_MASK)
    {
      fdv_adr = UnTag_FDV(word);
      Add_Monom(p, sign, 1, Tag_REF(fdv_adr));
      return TRUE;
    }

  if (tag_mask == TAG_INT_MASK)
    {
      n1 = UnTag_INT(word);
      if (n1 > MAX_COEF_FOR_SORT)
	sort = TRUE;

      Add_Cst_To_Poly(p, sign, n1);
      return TRUE;
    }

  if (tag_mask == TAG_REF_MASK)
    {
      if (vars_sp - vars_tbl >= VARS_STACK_SIZE)
	Pl_Err_Resource(pl_resource_too_big_fd_constraint);

      *vars_sp++ = word;
      Add_Monom(p, sign, 1, word);
      return TRUE;
    }

  if (tag_mask == TAG_ATM_MASK)
    {
      word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
      Pl_Unify_Value(e_word);
      Pl_Unify_Integer(0);
    type_error:
      Pl_Err_Type(pl_type_fd_evaluable, word);
    }

  if (tag_mask != TAG_STC_MASK)
    goto type_error;


  adr = UnTag_STC(word);

  f_n = Functor_And_Arity(adr);
  for (i = 0; i < NB_OF_OP; i++)
    if (arith_tbl[i] == f_n)
      break;

  le_word = Arg(adr, 0);
  re_word = Arg(adr, 1);

  switch (i)
    {
    case PLUS_1:
      e_word = le_word;
      goto terminal_rec;

    case PLUS_2:
      if (!Normalize(le_word, sign, p))
	return FALSE;
      e_word = re_word;
      goto terminal_rec;

    case MINUS_2:
      if (!Normalize(le_word, sign, p))
	return FALSE;
      e_word = re_word;
      sign = -sign;
      goto terminal_rec;

    case MINUS_1:
      e_word = le_word;
      sign = -sign;
      goto terminal_rec;

    case TIMES_2:
#ifdef DEVELOP_TIMES_2
#if 1				/* optimize frequent use: INT*VAR */
      DEREF(le_word, word, tag_mask);
      if (tag_mask != TAG_INT_MASK)
	goto any;

      n1 = UnTag_INT(word);

      if (n1 > MAX_COEF_FOR_SORT)
	sort = TRUE;

      DEREF(re_word, word, tag_mask);
      if (tag_mask != TAG_REF_MASK)
	{
	  if (tag_mask != TAG_FDV_MASK)
	    goto any;
	  else
	    {
	      fdv_adr = UnTag_FDV(word);
	      word = Tag_REF(fdv_adr);
	    }
	}
      Add_Monom(p, sign, n1, word);
      return TRUE;
    any:
#endif
      {
	Poly p1, p2;
	int i1, i2;

	New_Poly(p1);
	New_Poly(p2);

	if (!Normalize(le_word, 1, &p1) || !Normalize(re_word, 1, &p2))
	  return FALSE;

	Add_Cst_To_Poly(p, sign, p1.c * p2.c);

	for (i1 = 0; i1 < p1.nb_monom; i1++)
	  {
	    Add_Monom(p, sign, p1.m[i1].a * p2.c, p1.m[i1].x_word);
	    for (i2 = 0; i2 < p2.nb_monom; i2++)
	      if (!Add_Multiply_Monom(p, sign, p1.m + i1, p2.m + i2))
		return FALSE;
	  }

	for (i2 = 0; i2 < p2.nb_monom; i2++)
	  Add_Monom(p, sign, p2.m[i2].a * p1.c, p2.m[i2].x_word);

	return TRUE;
      }
#else
      if (!Load_Term_Into_Word(le_word, &word1) ||
	  !Load_Term_Into_Word(re_word, &word2))
	return FALSE;

      if (Tag_Is_INT(word1))
	{
	  n1 = UnTag_INT(word1);
	  if (Tag_Is_INT(word2))
	    {
	      n2 = UnTag_INT(word2);
	      n1 = n1 * n2;
	      Add_Cst_To_Poly(p, sign, n1);
	      return TRUE;
	    }

	  Add_Monom(p, sign, n1, word2);
	  return TRUE;
	}

      if (Tag_Is_INT(word2))
	{
	  n2 = UnTag_INT(word2);
	  Add_Monom(p, sign, n2, word1);
	  return TRUE;
	}


      word1 = (word1 == word2)
	? Push_Delayed_Cstr(DC_X2_EQ_Y, word1, 0, 0)
	: Push_Delayed_Cstr(DC_XY_EQ_Z, word1, word2, 0);

      Add_Monom(p, sign, 1, word1);
      return TRUE;
#endif

    case POWER_2:
      if (!Load_Term_Into_Word(le_word, &word1) ||
	  !Load_Term_Into_Word(re_word, &word2))
	return FALSE;

      if (Tag_Is_INT(word1))
	{
	  n1 = UnTag_INT(word1);
	  if (Tag_Is_INT(word2))
	    {
	      n2 = UnTag_INT(word2);
	      if ((n1 = Pl_Power(n1, n2)) < 0)
		return FALSE;

	      Add_Cst_To_Poly(p, sign, n1);
	      return TRUE;
	    }

	  if (n1 == 1)
	    {
	      Add_Cst_To_Poly(p, sign, 1);
	      return TRUE;
	    }

	  word = (n1 == 0)
	    ? Push_Delayed_Cstr(DC_ZERO_POWER_N_EQ_Y, word2, 0, 0)
	    : Push_Delayed_Cstr(DC_A_POWER_N_EQ_Y, word1, word2, 0);
	  goto end_power;
	}

      if (Tag_Mask_Of(word2) != TAG_INT_MASK)
	Pl_Err_Instantiation();
      else
	{
	  n2 = UnTag_INT(word2);
	  if (n2 == 0)
	    {
	      Add_Cst_To_Poly(p, sign, 1);
	      return TRUE;
	    }

	  word = (n2 == 1)
	    ? word1
	    : (n2 == 2)
	    ? Push_Delayed_Cstr(DC_X2_EQ_Y, word1, 0, 0)
	    : Push_Delayed_Cstr(DC_X_POWER_A_EQ_Y, word1, word2, 0);
	}
    end_power:
      Add_Monom(p, sign, 1, word);
      return TRUE;

    case MIN_2:
      if (!Load_Term_Into_Word(le_word, &word1) ||
	  !Load_Term_Into_Word(re_word, &word2))
	return FALSE;

      if (Tag_Is_INT(word1))
	{
	  n1 = UnTag_INT(word1);
	  if (Tag_Is_INT(word2))
	    {
	      n2 = UnTag_INT(word2);
	      n1 = math_min(n1, n2);
	      Add_Cst_To_Poly(p, sign, n1);
	      return TRUE;
	    }

	  word = Push_Delayed_Cstr(DC_MIN_X_A_EQ_Z, word2, word1, 0);
	  goto end_min;
	}

      if (Tag_Is_INT(word2))
	word = Push_Delayed_Cstr(DC_MIN_X_A_EQ_Z, word1, word2, 0);
      else
	word = Push_Delayed_Cstr(DC_MIN_X_Y_EQ_Z, word1, word2, 0);

    end_min:
      Add_Monom(p, sign, 1, word);
      return TRUE;

    case MAX_2:
      if (!Load_Term_Into_Word(le_word, &word1) ||
	  !Load_Term_Into_Word(re_word, &word2))
	return FALSE;

      if (Tag_Is_INT(word1))
	{
	  n1 = UnTag_INT(word1);
	  if (Tag_Is_INT(word2))
	    {
	      n2 = UnTag_INT(word2);
	      n1 = math_max(n1, n2);
	      Add_Cst_To_Poly(p, sign, n1);
	      return TRUE;
	    }

	  word = Push_Delayed_Cstr(DC_MAX_X_A_EQ_Z, word2, word1, 0);
	  goto end_max;
	}

      if (Tag_Is_INT(word2))
	word = Push_Delayed_Cstr(DC_MAX_X_A_EQ_Z, word1, word2, 0);
      else
	word = Push_Delayed_Cstr(DC_MAX_X_Y_EQ_Z, word1, word2, 0);

    end_max:
      Add_Monom(p, sign, 1, word);
      return TRUE;

    case DIST_2:
      if (!Load_Term_Into_Word(le_word, &word1) ||
	  !Load_Term_Into_Word(re_word, &word2))
	return FALSE;

      if (Tag_Is_INT(word1))
	{
	  n1 = UnTag_INT(word1);
	  if (Tag_Is_INT(word2))
	    {
	      n2 = UnTag_INT(word2);
	      n1 = (n1 >= n2) ? n1 - n2 : n2 - n1;
	      Add_Cst_To_Poly(p, sign, n1);
	      return TRUE;
	    }

	  word = Push_Delayed_Cstr(DC_ABS_X_MINUS_A_EQ_Z, word2, word1, 0);
	  goto end_dist;
	}

      if (Tag_Is_INT(word2))
	word = Push_Delayed_Cstr(DC_ABS_X_MINUS_A_EQ_Z, word1, word2, 0);
      else
	word = Push_Delayed_Cstr(DC_ABS_X_MINUS_Y_EQ_Z, word1, word2, 0);

    end_dist:
      Add_Monom(p, sign, 1, word);
      return TRUE;

    case QUOT_2:
      word3 = Make_Self_Ref(H);	/* word3 = remainder */
      Global_Push(word3);
      goto quot_rem;

    case REM_2:
      word3 = Make_Self_Ref(H);	/* word3 = remainder */
      Global_Push(word3);
      goto quot_rem;

    case QUOT_REM_3:
    quot_rem:
    if (!Load_Term_Into_Word(le_word, &word1) ||
	!Load_Term_Into_Word(re_word, &word2) ||
	(i == QUOT_REM_3 && !Load_Term_Into_Word(Arg(adr, 2), &word3)))
      return FALSE;

    if (Tag_Is_INT(word1))
      {
	n1 = UnTag_INT(word1);
	if (Tag_Is_INT(word2))
	  {
	    n2 = UnTag_INT(word2);
	    if (n2 == 0)
	      return FALSE;
	    n3 = n1 % n2;

	    if (i == QUOT_2 || i == QUOT_REM_3)
	      {
		if (i == QUOT_REM_3)
		  PRIM_CSTR_2(pl_x_eq_c, word3, word);
		else
		  H--;	/* recover word3 space */
		n3 = n1 / n2;
	      }

	    Add_Cst_To_Poly(p, sign, n3);
	    return TRUE;
	  }

	word = Push_Delayed_Cstr(DC_QUOT_REM_A_Y_R_EQ_Z, word1, word2,
				 word3);
	goto end_quot_rem;
      }

    if (Tag_Is_INT(word2))
      word = Push_Delayed_Cstr(DC_QUOT_REM_X_A_R_EQ_Z, word1, word2,
			       word3);
    else
      word = Push_Delayed_Cstr(DC_QUOT_REM_X_Y_R_EQ_Z, word1, word2,
			       word3);

    end_quot_rem:
    Add_Monom(p, sign, 1, (i == REM_2) ? word3 : word);
    return TRUE;

    case DIV_2:
      if (!Load_Term_Into_Word(le_word, &word1) ||
	  !Load_Term_Into_Word(re_word, &word2))
	return FALSE;

      if (Tag_Is_INT(word1))
	{
	  n1 = UnTag_INT(word1);
	  if (Tag_Is_INT(word2))
	    {
	      n2 = UnTag_INT(word2);
	      if (n2 == 0 || n1 % n2 != 0)
		return FALSE;
	      n1 /= n2;
	      Add_Cst_To_Poly(p, sign, n1);
	      return TRUE;
	    }

	  word = Push_Delayed_Cstr(DC_DIV_A_Y_EQ_Z, word1, word2, 0);
	  goto end_div;
	}

      if (Tag_Is_INT(word2))
	word = Push_Delayed_Cstr(DC_DIV_X_A_EQ_Z, word1, word2, 0);
      else
	word = Push_Delayed_Cstr(DC_DIV_X_Y_EQ_Z, word1, word2, 0);

    end_div:
      Add_Monom(p, sign, 1, word);
      return TRUE;

    default:
      word = Pl_Put_Structure(ATOM_CHAR('/'), 2);
      Pl_Unify_Atom(Functor(adr));
      Pl_Unify_Integer(Arity(adr));
      goto type_error;
    }

  return TRUE;
}
Example #7
0
/*-------------------------------------------------------------------------*
 * PL_COPY_CONTIGUOUS_TERM                                                 *
 *                                                                         *
 * Copy a contiguous term (dereferenced), the result is a contiguous term. *
 *-------------------------------------------------------------------------*/
void
Pl_Copy_Contiguous_Term(WamWord *dst_adr, WamWord *src_adr)
#define Old_Adr_To_New_Adr(adr)  ((dst_adr)+((adr)-(src_adr)))
{
    WamWord word, *adr;
    WamWord *q;
    int i;

terminal_rec:

    word = *src_adr;

    switch (Tag_Of(word))
    {
    case REF:
        adr = UnTag_REF(word);
        q = Old_Adr_To_New_Adr(adr);
        *dst_adr = Tag_REF(q);
        if (adr > src_adr)	/* only useful for Dont_Separate_Tag */
            Pl_Copy_Contiguous_Term(q, adr);
        return;

#ifndef NO_USE_FD_SOLVER
    case FDV:
        adr = UnTag_FDV(word);
        Fd_Copy_Variable(dst_adr, adr);
        return;
#endif

    case FLT:
        adr = UnTag_FLT(word);
        q = Old_Adr_To_New_Adr(adr);
        q[0] = adr[0];
#if WORD_SIZE == 32
        q[1] = adr[1];
#endif
        *dst_adr = Tag_FLT(q);
        return;

    case LST:
        adr = UnTag_LST(word);
        q = Old_Adr_To_New_Adr(adr);
        *dst_adr = Tag_LST(q);
        q = &Car(q);
        adr = &Car(adr);
        Pl_Copy_Contiguous_Term(q++, adr++);
        dst_adr = q;
        src_adr = adr;
        goto terminal_rec;

    case STC:
        adr = UnTag_STC(word);
        q = Old_Adr_To_New_Adr(adr);
        *dst_adr = Tag_STC(q);

        Functor_And_Arity(q) = Functor_And_Arity(adr);

        i = Arity(adr);

        q = &Arg(q, 0);
        adr = &Arg(adr, 0);
        while (--i)
            Pl_Copy_Contiguous_Term(q++, adr++);

        dst_adr = q;
        src_adr = adr;
        goto terminal_rec;

    default:
        *dst_adr = word;
        return;
    }
}
Example #8
0
/*-------------------------------------------------------------------------*
 * COPY_TERM_REC                                                           *
 *                                                                         *
 * p is the next address to use to store the rest of a term.               *
 *-------------------------------------------------------------------------*/
static void
Copy_Term_Rec(WamWord *dst_adr, WamWord *src_adr, WamWord **p)
{
    WamWord word, tag_mask;
    WamWord *adr;
    WamWord *q;
    int i;

terminal_rec:

    DEREF(*src_adr, word, tag_mask);

    switch (Tag_From_Tag_Mask(tag_mask))
    {
    case REF:
        adr = UnTag_REF(word);
        q = *p;
        if (adr < q && adr >= base_copy)	/* already a copy */
        {
            *dst_adr = word;
            return;
        }

        if (top_vars >= end_vars)
            Pl_Err_Representation(pl_representation_too_many_variables);

        *top_vars++ = word;	                /* word to restore    */
        *top_vars++ = (WamWord) adr;	        /* address to restore */
        *adr = *dst_adr = Tag_REF(dst_adr);	/* bind to a new copy */
        return;

#ifndef NO_USE_FD_SOLVER
    case FDV:
        adr = UnTag_FDV(word);
        q = *p;
        if (adr < q && adr >= base_copy)	/* already a copy */
        {
            *dst_adr = Tag_REF(adr);	/* since Dont_Separate_Tag */
            return;
        }

        if (top_vars >= end_vars)
            Pl_Err_Representation(pl_representation_too_many_variables);

        *top_vars++ = word;	        /* word to restore    */
        *top_vars++ = (WamWord) adr;	/* address to restore */
        q = *p;
        *p = q + Fd_Copy_Variable(q, adr);
        *adr = *dst_adr = Tag_REF(q);	/* bind to a new copy */
        return;
#endif

    case FLT:
        adr = UnTag_FLT(word);
        q = *p;
        q[0] = adr[0];
#if WORD_SIZE == 32
        q[1] = adr[1];
        *p = q + 2;
#else
        *p = q + 1;
#endif
        *dst_adr = Tag_FLT(q);
        return;

    case LST:
        adr = UnTag_LST(word);
        q = *p;
        *dst_adr = Tag_LST(q);

        *p = &Cdr(q) + 1;
        q = &Car(q);
        adr = &Car(adr);
        Copy_Term_Rec(q++, adr++, p);

        dst_adr = q;
        src_adr = adr;
        goto terminal_rec;

    case STC:
        adr = UnTag_STC(word);
        q = *p;
        *dst_adr = Tag_STC(q);

        Functor_And_Arity(q) = Functor_And_Arity(adr);

        i = Arity(adr);
        *p = &Arg(q, i - 1) + 1;

        q = &Arg(q, 0);
        adr = &Arg(adr, 0);
        while (--i)
            Copy_Term_Rec(q++, adr++, p);

        dst_adr = q;
        src_adr = adr;
        goto terminal_rec;

    default:
        *dst_adr = word;
        return;
    }
}