/*************************************************************************
*									 *
*	 YAP Prolog 	%W% %G%		*
*									 *
*	Yap Prolog was developed at NCCUP - Universidade do Porto	 *
*									 *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997	 *
*									 *
**************************************************************************
*									 *
* File:		clause.h						 *
* Last rev:								 *
* mods:									 *
* comments:	clause info						 *
*									 *
*************************************************************************/

#include "Yatom.h"
#include "YapHeap.h"

/* consulting files */

typedef union CONSULT_OBJ {
  char *filename;
  int mode;
  Prop  p;
  UInt c;
} consult_obj;

/* Either we are assembling clauses or indexing code */

#define ASSEMBLING_CLAUSE	0
#define ASSEMBLING_INDEX	1
#define ASSEMBLING_EINDEX	2

#define NextDynamicClause(X)	(((yamop *)X)->u.Otapl.d)

#define PredFirstClause		0
#define PredMiddleClause	1
#define PredLastClause		2

typedef struct logic_upd_index {
  CELL             ClFlags;
  UInt             ClRefCount;
#if defined(YAPOR) || defined(THREADS)
  /* A lock for manipulating the clause */
  //  lockvar          ClLock;
#endif
  UInt		   ClSize;
  struct logic_upd_index *ParentIndex;
  struct logic_upd_index *SiblingIndex;
  struct logic_upd_index *PrevSiblingIndex;
  struct logic_upd_index *ChildIndex;
  /* The instructions, at least one of the form sl */
  PredEntry *ClPred;
  yamop            ClCode[MIN_ARRAY];
} LogUpdIndex;

/* The ordering of the first 3 fields should be compatible with dbrefs */
typedef struct logic_upd_clause {
  Functor Id;		/* allow pointers to this struct to id  */
			/*   as dbref                           */
  /* A set of flags describing info on the clause */
  /* A set of flags describing info on the clause */
  CELL             ClFlags;
#if defined(YAPOR) || defined(THREADS)
  /* A lock for manipulating the clause */
  //  lockvar          ClLock;
#endif
  UInt		  ClSize;
  /* extra clause information for logical update indices and facts */
  /* indices that may still backtrack to this clause */
  UInt             ClRefCount;
  /* data for clauses  with environments */
  yamop           *ClExt;
  union {
    DBTerm          *ClSource;
    Int             ClLine;
  } lusl;
  /* doubly linked list of clauses */
  struct logic_upd_clause   *ClPrev, *ClNext;
  /* parent pointer */
  PredEntry   *ClPred;
  UInt             ClTimeStart, ClTimeEnd;
  /* The instructions, at least one of the form sl */
  yamop            ClCode[MIN_ARRAY];
} LogUpdClause;

#include "inline-only.h"
INLINE_ONLY inline EXTERN int VALID_TIMESTAMP(UInt, struct logic_upd_clause *);

INLINE_ONLY inline EXTERN int
VALID_TIMESTAMP(UInt timestamp, struct logic_upd_clause *cl)
{
  return IN_BETWEEN(cl->ClTimeStart, timestamp, cl->ClTimeEnd);
}

typedef struct dynamic_clause {
  /* A set of flags describing info on the clause */
  CELL            ClFlags;
#if defined(YAPOR) || defined(THREADS)
  /* A lock for manipulating the clause */
  lockvar          ClLock;
#endif
  UInt		   ClSize;
  Int              ClLine;
  UInt             ClRefCount;
  yamop              *ClPrevious;     /* immediate update clause */
  /* The instructions, at least one of the form sl */
  yamop            ClCode[MIN_ARRAY];
} DynamicClause;

typedef struct static_index {
  /* A set of flags describing info on the clause */
  CELL            ClFlags;
  UInt		  ClSize;
  struct static_index *SiblingIndex;
  struct static_index *ChildIndex;
  /* The instructions, at least one of the form sl */
  PredEntry *ClPred;
  yamop            ClCode[MIN_ARRAY];
} StaticIndex;

typedef struct static_clause {
  /* A set of flags describing info on the clause */
  CELL            ClFlags;
  UInt		  ClSize;
  union {
    DBTerm         *ClSource;
    Int             ClLine;
  } usc;
  struct static_clause   *ClNext;
  /* The instructions, at least one of the form sl */
  yamop            ClCode[MIN_ARRAY];
} StaticClause;

typedef struct static_mega_clause {
  /* A set of flags describing info on the clause */
  CELL            ClFlags;
  UInt		  ClSize;
  PredEntry      *ClPred;
  UInt            ClItemSize;
  Int             ClLine;
  struct  static_mega_clause *ClNext;
  /* The instructions, at least one of the form sl */
  yamop            ClCode[MIN_ARRAY];
} MegaClause;

typedef union clause_obj {
  struct logic_upd_clause luc;
  struct logic_upd_index lui;
  struct dynamic_clause ic;
  struct static_clause sc;
  struct static_mega_clause mc;
  struct static_index si;
} ClauseUnion;

typedef union clause_ptr {
  struct logic_upd_clause *luc;
  struct logic_upd_index *lui;
  struct dynamic_clause *ic;
  struct static_clause *sc;
  struct static_mega_clause *mc;
  struct static_index *si;
} ClausePointer;

typedef struct index_t {
  struct index_t *next, *prev;
  UInt nels;
  UInt arity;
  PredEntry *ap;
  CELL bmap;
  int is_key;
  int is_udi;
  UInt ncollisions;
  UInt max_col_count;
  UInt ntrys;
  UInt nentries;
  UInt hsize;
  BITS32 *key;
  CELL *cls, *bcls;
  BITS32 *links;
  size_t size;
  yamop *code;
  BITS32 *udi_data;
  void *udi_first, *udi_next;
  UInt udi_free_args;
  UInt udi_arg;
} Index_t;

INLINE_ONLY EXTERN inline BITS32 EXO_ADDRESS_TO_OFFSET(struct index_t *it, CELL *ptr);

INLINE_ONLY EXTERN inline   BITS32
EXO_ADDRESS_TO_OFFSET(struct index_t *it, CELL* ptr)
{
  return (ptr-it->cls)/it->arity+1;
}

INLINE_ONLY EXTERN inline  CELL *EXO_OFFSET_TO_ADDRESS(struct index_t *it, BITS32  off);

INLINE_ONLY EXTERN inline   CELL *
EXO_OFFSET_TO_ADDRESS(struct index_t *it, BITS32  off)
{
  if (off == 0L) 
    return NULL;
  return (it->cls)+(off-1)*it->arity;
}

INLINE_ONLY EXTERN inline  BITS32 ADDRESS_TO_LINK(struct index_t *it, BITS32 *ptr);

INLINE_ONLY EXTERN inline  BITS32
ADDRESS_TO_LINK(struct index_t *it, BITS32* ptr)
{
  return ptr-it->links;
}

INLINE_ONLY EXTERN inline BITS32 *LINK_TO_ADDRESS(struct index_t *it, BITS32  off);

INLINE_ONLY EXTERN inline   BITS32 *
LINK_TO_ADDRESS(struct index_t *it, BITS32  off)
{
  return it->links+off;
}

typedef void (*CRefitExoIndex)(struct index_t **ip, UInt b[] USES_REGS);
typedef yamop *  (*CEnterExoIndex)(struct index_t *it USES_REGS);
typedef int     (*CRetryExoIndex)(struct index_t *it USES_REGS);

typedef struct dbterm_list {
  /* a list of dbterms associated with a clause */
  DBTerm *dbterms;
  yamop *clause_code;
  PredEntry *p;
  struct dbterm_list *next_dbl;
} DBTermList;

#define ClauseCodeToDynamicClause(p)    ((DynamicClause *)((CODEADDR)(p)-(CELL)(((DynamicClause *)NULL)->ClCode)))
#define ClauseCodeToStaticClause(p)    ((StaticClause *)((CODEADDR)(p)-(CELL)(((StaticClause *)NULL)->ClCode)))
#define ClauseCodeToLogUpdClause(p)    ((LogUpdClause *)((CODEADDR)(p)-(CELL)(((LogUpdClause *)NULL)->ClCode)))
#define ClauseCodeToMegaClause(p)    ((MegaClause *)((CODEADDR)(p)-(CELL)(((MegaClause *)NULL)->ClCode)))
#define ClauseCodeToLogUpdIndex(p)    ((LogUpdIndex *)((CODEADDR)(p)-(CELL)(((LogUpdIndex *)NULL)->ClCode)))
#define ClauseCodeToStaticIndex(p)    ((StaticIndex *)((CODEADDR)(p)-(CELL)(((StaticIndex *)NULL)->ClCode)))

#define ClauseFlagsToDynamicClause(p)    ((DynamicClause *)(p))
#define ClauseFlagsToLogUpdClause(p)     ((LogUpdClause *)((CODEADDR)(p)-(CELL)(&(((LogUpdClause *)NULL)->ClFlags))))
#define ClauseFlagsToLogUpdIndex(p)      ((LogUpdIndex *)((CODEADDR)(p)-(CELL)(&(((LogUpdIndex *)NULL)->ClFlags))))
#define ClauseFlagsToStaticClause(p)     ((StaticClause *)(p))

#define DynamicFlags(X)		(ClauseCodeToDynamicClause(X)->ClFlags)

#define DynamicLock(X)		(ClauseCodeToDynamicClause(X)->ClLock)

#if MULTIPLE_STACKS
#define INIT_CLREF_COUNT(X) (X)->ClRefCount = 0
#define  INC_CLREF_COUNT(X) (X)->ClRefCount++
#define  DEC_CLREF_COUNT(X) (X)->ClRefCount--

#define        CL_IN_USE(X) ((X)->ClRefCount)
#else
#define INIT_CLREF_COUNT(X)
#define  INC_CLREF_COUNT(X) 
#define  DEC_CLREF_COUNT(X) 
#define        CL_IN_USE(X) ((X)->ClFlags & InUseMask || (X)->ClRefCount)
#endif

/* amasm.c */
wamreg	Yap_emit_x(CELL);
COUNT   Yap_compile_cmp_flags(PredEntry *);
void    Yap_InitComma(void);

/* cdmgr.c */
void	Yap_IPred(PredEntry *, UInt, yamop *);
int	Yap_addclause(Term,yamop *,int,Term,Term*);
void	Yap_add_logupd_clause(PredEntry *,LogUpdClause *,int);
void	Yap_kill_iblock(ClauseUnion *,ClauseUnion *,PredEntry *);
void	Yap_EraseStaticClause(StaticClause *, PredEntry *, Term);
ClauseUnion *Yap_find_owner_index(yamop *, PredEntry *);

/* dbase.c */
void	Yap_ErCl(DynamicClause *);
void	Yap_ErLogUpdCl(LogUpdClause *);
void    Yap_ErLogUpdIndex(LogUpdIndex *);
Int	Yap_Recordz(Atom, Term);
Int     Yap_db_nth_recorded( PredEntry *, Int USES_REGS );
Int     Yap_unify_immediate_ref(DBRef ref USES_REGS );

/* exec.c */
Term    Yap_cp_as_integer(choiceptr);

/* index.c */
yamop   *Yap_PredIsIndexable(PredEntry *, UInt, yamop *);
yamop   *Yap_ExpandIndex(PredEntry *, UInt);
void     Yap_CleanUpIndex(struct logic_upd_index *);
void     Yap_CleanKids(struct logic_upd_index *);
void     Yap_AddClauseToIndex(PredEntry *,yamop *,int);
void     Yap_RemoveClauseFromIndex(PredEntry *,yamop *);
LogUpdClause  *Yap_NthClause(PredEntry *,Int);
LogUpdClause  *Yap_FollowIndexingCode(PredEntry *,yamop *, Term *, yamop *,yamop *);

/* exo.c */
yamop    *Yap_ExoLookup(PredEntry *ap USES_REGS);
CELL    Yap_NextExo(choiceptr cpt, struct index_t *it);

#if USE_THREADED_CODE

#define OP_HASH_SIZE 2048

static inline int
rtable_hash_op(OPCODE opc, int hash_mask) {
  return((((CELL)opc) >> 3) & hash_mask);
}

/* given an opcode find the corresponding opnumber. This should make
   switches on ops a much easier operation */
static inline op_numbers
Yap_op_from_opcode(OPCODE opc)
{
  int j = rtable_hash_op(opc,OP_HASH_SIZE-1);

  while (OP_RTABLE[j].opc != opc) {
    if (!OP_RTABLE[j].opc)
      return _Nstop;
    if (j == OP_HASH_SIZE-1) {
      j = 0;
    } else {
      j++;
    }
  }
  return OP_RTABLE[j].opnum;
}
#else
static inline op_numbers
Yap_op_from_opcode(OPCODE opc)
{
  return((op_numbers)opc);
}
#endif /* USE_THREADED_CODE */

#if defined(YAPOR) || defined(THREADS)
static inline int same_lu_block(yamop **, yamop *);

static inline int
same_lu_block(yamop **paddr, yamop *p)
{
  yamop *np = *paddr;
  if (np != p) {
    OPCODE jmp_op = Yap_opcode(_jump_if_nonvar);

    while (np->opc == jmp_op) {
      np = NEXTOP(np, xll);
      if (np == p) return TRUE;
    }
    return FALSE;
  } else {
    return TRUE;
  }
}
#endif

#define Yap_MkStaticRefTerm(cp, ap) __Yap_MkStaticRefTerm((cp), (ap) PASS_REGS)

static inline Term 
__Yap_MkStaticRefTerm(StaticClause *cp, PredEntry *ap USES_REGS)
{
  Term t[2];
  t[0] = MkIntegerTerm((Int)cp);
  t[1] = MkIntegerTerm((Int)ap);
  return Yap_MkApplTerm(FunctorStaticClause,2,t);
}

static inline StaticClause *
Yap_ClauseFromTerm(Term t)
{
  return (StaticClause *)IntegerOfTerm(ArgOfTerm(1,t));
}

#define Yap_MkMegaRefTerm(ap, ipc) __Yap_MkMegaRefTerm((ap), (ipc) PASS_REGS)

static inline Term 
__Yap_MkMegaRefTerm(PredEntry *ap,yamop *ipc USES_REGS)
{
  Term t[2];
  t[0] = MkIntegerTerm((Int)ap);
  t[1] = MkIntegerTerm((Int)ipc);
  return Yap_MkApplTerm(FunctorMegaClause,2,t);
}

static inline yamop * 
Yap_MegaClauseFromTerm(Term t)
{
  return (yamop *)IntegerOfTerm(ArgOfTerm(2,t));
}

static inline PredEntry * 
Yap_MegaClausePredicateFromTerm(Term t)
{
  return (PredEntry *)IntegerOfTerm(ArgOfTerm(1,t));
}

#define Yap_MkExoRefTerm(ap, i) __Yap_MkExoRefTerm((ap), (i) PASS_REGS)

static inline Term 
__Yap_MkExoRefTerm(PredEntry *ap,Int i USES_REGS)
{
  Term t[2];
  t[0] = MkIntegerTerm((Int)ap);
  t[1] = MkIntegerTerm((Int)i);
  return Yap_MkApplTerm(FunctorExoClause,2,t);
}

static inline Int 
Yap_ExoClauseFromTerm(Term t)
{
  return IntegerOfTerm(ArgOfTerm(2,t));
}

static inline PredEntry * 
Yap_ExoClausePredicateFromTerm(Term t)
{
  return (PredEntry *)IntegerOfTerm(ArgOfTerm(1,t));
}

#define DEAD_REF(ref) FALSE


typedef enum {
  FIND_PRED_FROM_ANYWHERE,
  FIND_PRED_FROM_CP,
  FIND_PRED_FROM_ENV
} find_pred_type;

Int	     Yap_PredForCode(yamop *, find_pred_type, Atom *, UInt *, Term *);
PredEntry *Yap_PredEntryForCode(yamop *, find_pred_type, CODEADDR *, CODEADDR *);
LogUpdClause   *Yap_new_ludbe(Term, PredEntry *, UInt);
Term        Yap_LUInstance(LogUpdClause *, UInt);

/* udi.c */
int          Yap_new_udi_clause(PredEntry *, yamop *, Term);
yamop       *Yap_udi_search(PredEntry *);

#ifdef DEBUG
void    Yap_bug_location(yamop *);
#endif

#if  LOW_PROF
void	Yap_InformOfRemoval(void *);
void	Yap_dump_code_area_for_profiler(void);
#else
#define	Yap_InformOfRemoval(X)
#endif