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absmi.c

/*************************************************************************
*                                                      *
*      YAP Prolog                                            *
*                                                      *
*     Yap Prolog was developed at NCCUP - Universidade do Porto    *
*                                                      *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997       *
*                                                      *
**************************************************************************
*                                                      *
* File:           absmi.c                                          *
* comments: Portable abstract machine interpreter                    *
* Last rev:     $Date: 2006/04/12 17:14:58 $,$Author: rslopes $                                  *
* $Log: absmi.c,v $
* Revision 1.200  2006/04/12 17:14:58  rslopes
* fix needed by the EAM engine
*
* Revision 1.199  2006/04/12 15:51:23  rslopes
* small fixes
*
* Revision 1.198  2006/03/30 01:11:09  vsc
* fix nasty variable shunting bug in garbage collector :-(:wq
*
* Revision 1.197  2006/03/24 17:13:41  rslopes
* New update to BEAM engine.
* BEAM now uses YAP Indexing (JITI)
*
* Revision 1.196  2006/03/03 23:10:47  vsc
* fix MacOSX interrupt handling
* fix using Yap files as Yap scripts.
*
* Revision 1.195  2006/02/01 13:28:56  vsc
* bignum support fixes
*
* Revision 1.194  2006/01/26 19:13:24  vsc
* avoid compilation issues with lack of gmp (Remko Troncon)
*
* Revision 1.193  2006/01/18 15:34:53  vsc
* avoid sideffects from MkBigInt
*
* Revision 1.192  2006/01/17 14:10:40  vsc
* YENV may be an HW register (breaks some tabling code)
* All YAAM instructions are now brackedted, so Op introduced an { and EndOp introduces an }. This is because Ricardo assumes that.
* Fix attvars when COROUTING is undefined.
*
* Revision 1.191  2006/01/02 02:16:17  vsc
* support new interface between YAP and GMP, so that we don't rely on our own
* allocation routines.
* Several big fixes.
*
* Revision 1.190  2005/12/23 00:20:13  vsc
* updates to gprof
* support for __POWER__
* Try to saveregs before longjmp.
*
* Revision 1.189  2005/12/17 03:25:38  vsc
* major changes to support online event-based profiling
* improve error discovery and restart on scanner.
*
* Revision 1.188  2005/12/05 17:16:10  vsc
* write_depth/3
* overflow handlings and garbage collection
* Several ipdates to CLPBN
* dif/2 could be broken in the presence of attributed variables.
*
* Revision 1.187  2005/11/26 02:57:25  vsc
* improvements to debugger
* overflow fixes
* reading attvars from DB was broken.
*
* Revision 1.186  2005/11/23 03:01:32  vsc
* fix several bugs in save/restore.b
*
* Revision 1.185  2005/11/18 18:48:51  tiagosoares
* support for executing c code when a cut occurs
*
* Revision 1.184  2005/11/15 00:50:49  vsc
* fixes for stack expansion and garbage collection under tabling.
*
* Revision 1.183  2005/11/07 15:35:47  vsc
* fix bugs in garbage collection of tabling.
*
* Revision 1.182  2005/11/05 03:02:33  vsc
* get rid of unnecessary ^ in setof
* Found bug in comparisons
*
* Revision 1.181  2005/11/04 15:39:14  vsc
* absmi should PREG, never P!!
*
* Revision 1.180  2005/10/28 17:38:49  vsc
* sveral updates
*
* Revision 1.179  2005/10/18 17:04:43  vsc
* 5.1:
* - improvements to GC
*    2 generations
*    generic speedups
* - new scheme for attvars
*    - hProlog like interface also supported
* - SWI compatibility layer
*    - extra predicates
*    - global variables
*    - moved to Prolog module
* - CLP(R) by Leslie De Koninck, Tom Schrijvers, Cristian Holzbaur, Bart
* Demoen and Jan Wielemacker
* - load_files/2
*
* from 5.0.1
*
* - WIN32 missing include files (untested)
* - -L trouble (my thanks to Takeyuchi Shiramoto-san)!
* - debugging of backtrable user-C preds would core dump.
* - redeclaring a C-predicate as Prolog core dumps.
* - badly protected  YapInterface.h.
* - break/0 was failing at exit.
* - YAP_cut_fail and YAP_cut_succeed were different from manual.
* - tracing through data-bases could core dump.
* - cut could break on very large computations.
* - first pass at BigNum issues (reported by Roberto).
* - debugger could get go awol after fail port.
* - weird message on wrong debugger option.
*
* Revision 1.178  2005/10/15 17:05:23  rslopes
* enable profiling on amd64
*
* Revision 1.177  2005/09/09 17:24:37  vsc
* a new and hopefully much better implementation of atts.
*
* Revision 1.176  2005/09/08 22:06:44  rslopes
* BEAM for YAP update...
*
* Revision 1.175  2005/08/12 17:00:00  ricroc
* TABLING FIX: support for incomplete tables
*
* Revision 1.174  2005/08/05 14:55:02  vsc
* first steps to allow mavars with tabling
* fix trailing for tabling with multiple get_cons
*
* Revision 1.173  2005/08/04 15:45:49  ricroc
* TABLING NEW: support to limit the table space size
*
* Revision 1.172  2005/08/02 03:09:48  vsc
* fix debugger to do well nonsource predicates.
*
* Revision 1.171  2005/08/01 15:40:36  ricroc
* TABLING NEW: better support for incomplete tabling
*
* Revision 1.170  2005/07/06 19:33:51  ricroc
* TABLING: answers for completed calls can now be obtained by loading (new option) or executing (default) them from the trie data structure.
*
* Revision 1.169  2005/07/06 15:10:01  vsc
* improvements to compiler: merged instructions and fixes for ->
*
* Revision 1.168  2005/06/04 07:27:33  ricroc
* long int support for tabling
*
* Revision 1.167  2005/06/03 08:26:31  ricroc
* float support for tabling
*
* Revision 1.166  2005/06/01 20:25:22  vsc
* == and \= should not need a choice-point in ->
*
* Revision 1.165  2005/06/01 14:02:45  vsc
* get_rid of try_me?, retry_me? and trust_me? instructions: they are not
* significantly used nowadays.
*
* Revision 1.164  2005/05/26 18:07:32  vsc
* fix warning
*
* Revision 1.163  2005/04/10 04:01:07  vsc
* bug fixes, I hope!
*
* Revision 1.162  2005/04/07 17:48:53  ricroc
* Adding tabling support for mixed strategy evaluation (batched and local scheduling)
*   UPDATE: compilation flags -DTABLING_BATCHED_SCHEDULING and -DTABLING_LOCAL_SCHEDULING removed. To support tabling use -DTABLING in the Makefile or --enable-tabling in configure.
*   NEW: yap_flag(tabling_mode,MODE) changes the tabling execution mode of all tabled predicates to MODE (batched, local or default).
*   NEW: tabling_mode(PRED,MODE) changes the default tabling execution mode of predicate PRED to MODE (batched or local).
*
* Revision 1.161  2005/03/13 06:26:09  vsc
* fix excessive pruning in meta-calls
* fix Term->int breakage in compiler
* improve JPL (at least it does something now for amd64).
*
* Revision 1.160  2005/03/07 17:49:14  vsc
* small fixes
*
* Revision 1.159  2005/03/04 20:29:55  ricroc
* bug fixes for YapTab support
*
* Revision 1.158  2005/03/01 22:25:07  vsc
* fix pruning bug
* make DL_MALLOC less enthusiastic about walking through buckets.
*
* Revision 1.157  2005/02/08 18:04:17  vsc
* library_directory may not be deterministic (usually it isn't).
*
* Revision 1.156  2005/01/13 05:47:25  vsc
* lgamma broke arithmetic optimisation
* integer_y has type y
* pass original source to checker (and maybe even use option in parser)
* use warning mechanism for checker messages.
*
* Revision 1.155  2004/12/28 22:20:34  vsc
* some extra bug fixes for trail overflows: some cannot be recovered that easily,
* some can.
*
* Revision 1.154  2004/12/05 05:01:21  vsc
* try to reduce overheads when running with goal expansion enabled.
* CLPBN fixes
* Handle overflows when allocating big clauses properly.
*
* Revision 1.153  2004/11/19 22:08:35  vsc
* replace SYSTEM_ERROR by out OUT_OF_WHATEVER_ERROR whenever appropriate.
*
* Revision 1.152  2004/11/19 17:14:12  vsc
* a few fixes for 64 bit compiling.
*
* Revision 1.151  2004/11/04 18:22:28  vsc
* don't ever use memory that has been freed (that was done by LU).
* generic fixes for WIN32 libraries
*
* Revision 1.150  2004/10/26 20:15:36  vsc
* More bug fixes for overflow handling
*
* Revision 1.149  2004/10/14 22:14:52  vsc
* don't use a cached version of ARG1 in choice-points
*
* Revision 1.148  2004/09/30 21:37:40  vsc
* fixes for thread support
*
* Revision 1.147  2004/09/30 19:51:53  vsc
* fix overflow from within clause/2
*
* Revision 1.146  2004/09/27 20:45:02  vsc
* Mega clauses
* Fixes to sizeof(expand_clauses) which was being overestimated
* Fixes to profiling+indexing
* Fixes to reallocation of memory after restoring
* Make sure all clauses, even for C, end in _Ystop
* Don't reuse space for Streams
* Fix Stream_F on StreaNo+1
*
* Revision 1.145  2004/09/17 20:47:35  vsc
* fix some overflows recorded.
*
* Revision 1.144  2004/09/17 19:34:49  vsc
* simplify frozen/2
*
* Revision 1.143  2004/08/16 21:02:04  vsc
* more fixes for !
*
* Revision 1.142  2004/08/11 16:14:51  vsc
* whole lot of fixes:
*   - memory leak in indexing
*   - memory management in WIN32 now supports holes
*   - extend Yap interface, more support for SWI-Interface
*   - new predicate mktime in system
*   - buffer console I/O in WIN32
*
* Revision 1.141  2004/07/23 21:08:44  vsc
* windows fixes
*
* Revision 1.140  2004/07/22 21:32:20  vsc
* debugger fixes
* initial support for JPL
* bad calls to garbage collector and gc
* debugger fixes
*
* Revision 1.139  2004/07/03 03:29:24  vsc
* make it compile again on non-linux machines
*
* Revision 1.138  2004/06/29 19:04:40  vsc
* fix multithreaded version
* include new version of Ricardo's profiler
* new predicat atomic_concat
* allow multithreaded-debugging
* small fixes
*
* Revision 1.137  2004/06/23 17:24:19  vsc
* New comment-based message style
* Fix thread support (at least don't deadlock with oneself)
* small fixes for coroutining predicates
* force Yap to recover space in arrays of dbrefs
* use private predicates in debugger.
*
* Revision 1.136  2004/06/17 22:07:22  vsc
* bad bug in indexing code.
*
* Revision 1.135  2004/06/09 03:32:02  vsc
* fix bugs
*
* Revision 1.134  2004/06/05 03:36:59  vsc
* coroutining is now a part of attvars.
* some more fixes.
*
* Revision 1.133  2004/05/13 20:54:57  vsc
* debugger fixes
* make sure we always go back to current module, even during initizlization.
*
* Revision 1.132  2004/04/29 03:45:49  vsc
* fix garbage collection in execute_tail
*
* Revision 1.131  2004/04/22 20:07:02  vsc
* more fixes for USE_SYSTEM_MEMORY
*
* Revision 1.130  2004/04/22 03:24:17  vsc
* trust_logical should protect the last clause, otherwise it cannot
* jump there.
*
* Revision 1.129  2004/04/16 19:27:30  vsc
* more bug fixes
*
* Revision 1.128  2004/04/14 19:10:22  vsc
* expand_clauses: keep a list of clauses to expand
* fix new trail scheme for multi-assignment variables
*
* Revision 1.127  2004/03/31 01:03:09  vsc
* support expand group of clauses
*
* Revision 1.126  2004/03/19 11:35:42  vsc
* trim_trail for default machine
* be more aggressive about try-retry-trust chains.
*    - handle cases where block starts with a wait
*    - don't use _killed instructions, just let the thing rot by itself.
*
* Revision 1.125  2004/03/10 14:59:54  vsc
* optimise -> for type tests
*
* Revision 1.124  2004/03/08 19:31:01  vsc
* move to 4.5.3
*                                                      *
*                                                      *
*************************************************************************/


#define IN_ABSMI_C 1

#include "absmi.h"
#include "heapgc.h"

#ifdef CUT_C
#include "cut_c.h"
#endif

inline static Functor
AritFunctorOfTerm(Term t) {
  if (IsVarTerm(t)) {
    return(FunctorDBRef);
  }
  if (IsApplTerm(t)) {
    return(FunctorOfTerm(t));
  } else {
    if (IsIntTerm(t))
      return(FunctorLongInt);
    else
      return(FunctorDBRef);
  }
}

#define TMP_BIG()  Yap_BigTmp
#define RINT(v)     return(MkIntegerTerm(v))
#define RFLOAT(v)   return(MkFloatTerm(v))
#if USE_GMP

#define RBIG(v)     return(rbig(v))

static inline Term rbig(MP_INT *big)
{
  Term t = Yap_MkBigIntTerm(big);
  mpz_clear(big);
  return t;
}
#endif

#define RERROR()    return(TermNil)

#define ArithIEval(t,v)     Yap_Eval(Deref(t),v)

#define E_FUNC   Term
#define E_ARGS   
#define USE_E_ARGS   

#include "arith2.h"

#ifdef COROUTINING
/*
  Imagine we are interrupting the execution, say, because we have a spy
   point or because we have goals to wake up. This routine saves the current
   live temporary registers into a structure pointed to by register ARG1.
   The registers are then recovered by a nasty builtin
   called 
*/
static Term
push_live_regs(yamop *pco)
{
  CELL *lab = (CELL *)(pco->u.l.l);
  CELL max = lab[0];
  CELL curr = lab[1];
  CELL *start = H;
  Int tot = 0;

  if (max) {
    CELL i;

    lab += 2;
    H++;
    for (i=0; i <= max; i++) {
      if (i == 8*CellSize) {
      curr = lab[0];
      lab++;
      }
      if (curr & 1) {
      CELL d1;

      tot+=2;
      H[0] = MkIntTerm(i);
      d1 = XREGS[i];
      deref_head(d1, wake_up_unk);
      wake_up_nonvar:
      /* just copy it to the heap */
      H[1] = d1;
      H += 2;
      continue;

      {
        CELL *pt0;
        deref_body(d1, pt0, wake_up_unk, wake_up_nonvar);
        /* bind it, in case it is a local variable */
        if (pt0 <= H) {
          /* variable is safe */
          H[1] = (CELL)pt0;
        } else {
          d1 = Unsigned(H+1);
          RESET_VARIABLE(H+1);
          Bind_Local(pt0, d1);
        }
      }
      H += 2;
      }
      curr >>= 1;
    }
    start[0] = (CELL)Yap_MkFunctor(AtomTrue, tot);
    return(AbsAppl(start));
  } else {
    return(TermNil);
  }
}
#endif

#if defined(ANALYST) || defined(DEBUG)

char *Yap_op_names[_std_top + 1] =
{
#define OPCODE(OP,TYPE) #OP
#include "YapOpcodes.h"
#undef  OPCODE
};

#endif


Int 
Yap_absmi(int inp)
{

#if BP_FREE
  /* some function might be using bp for an internal variable, it is the
     callee's responsability to save it */
  yamop* PCBACKUP = P1REG;
#endif

#ifdef LONG_LIVED_REGISTERS
  register CELL d0, d1;
  register CELL *pt0, *pt1;

#endif /* LONG_LIVED_REGISTERS */
  
#if SHADOW_P 
  register yamop *PREG = P;
#endif /* SHADOW_P */

#if SHADOW_CP
  register yamop *CPREG = CP;
#endif /* SHADOW_CP */

#if SHADOW_HB
  register CELL *HBREG = HB;
#endif /* SHADOW_HB */

#if SHADOW_Y
  register CELL *YREG = Yap_REGS.YENV_;
#endif /* SHADOW_Y */

#if SHADOW_S
  register CELL *SREG = Yap_REGS.S_;
#else
#define SREG S
#endif /* SHADOW_S */

  /* The indexing register so that we will not destroy ARG1 without
   * reason */
#define I_R (XREGS[0])

#if USE_THREADED_CODE
/************************************************************************/
/*     Abstract Machine Instruction Address Table                       */
/*  This must be declared inside the function. We use the asm directive */
/* to make it available outside this function                           */
/************************************************************************/
  static void *OpAddress[] =
  {
#define OPCODE(OP,TYPE) && OP
#include "YapOpcodes.h"
#undef  OPCODE
  };

#endif /* USE_THREADED_CODE */

#if SHADOW_REGS

  /* work with a local pointer to the registers */
  register REGSTORE *regp = &Yap_REGS;

#endif /* SHADOW_REGS */

#if PUSH_REGS

/* useful on a X86 with -fomit-frame-pointer optimisation */
  /* The idea is to push REGS onto the X86 stack frame */

  /* first allocate local space */
  REGSTORE absmi_regs;
  REGSTORE *old_regs = Yap_regp;

#endif /* PUSH_REGS */

#ifdef BEAM
  CELL OLD_B=B;
  extern PredEntry *bpEntry;
  if (inp==-9000) {
#if PUSH_REGS
    old_regs = &Yap_REGS;
    init_absmi_regs(&absmi_regs);
    Yap_regp = &absmi_regs;
#endif
    CACHE_A1();
    PREG=bpEntry->CodeOfPred;
    JMPNext();                /* go execute instruction at PREG */
  }

#endif


#if USE_THREADED_CODE
  /* absmadr */
  if (inp > 0) {
    Yap_ABSMI_OPCODES = OpAddress;
#if BP_FREE
    P1REG = PCBACKUP;
#endif
    return(0);
  }
#endif /* USE_THREADED_CODE */

#if PUSH_REGS
  old_regs = &Yap_REGS;

  /* done, let us now initialise this space */
  init_absmi_regs(&absmi_regs);

  /* the registers are all set up, let's swap */
#ifdef THREADS
  pthread_setspecific(Yap_yaamregs_key, (const void *)&absmi_regs);  
  ThreadHandle[worker_id].current_yaam_regs = &absmi_regs;
#else
  Yap_regp = &absmi_regs;
#endif
#undef Yap_REGS
#define Yap_REGS absmi_regs

#endif /* PUSH_REGS */

#if SHADOW_REGS

  /* use regp as a copy of REGS */
  regp = &Yap_REGS;

#ifdef REGS
#undef REGS
#endif
#define REGS (*regp)

#endif /* SHADOW_REGS */

  setregs();

  CACHE_A1();

 reset_absmi:
  
  SP = SP0;

#if USE_THREADED_CODE
  JMPNext();                  /* go execute instruction at P          */

#else
  /* when we start we are not in write mode */

  {
    op_numbers opcode = _Ystop;
    op_numbers old_op;
#ifdef DEBUG_XX
    unsigned long ops_done;
#endif

    goto nextop;

  nextop_write:

    old_op = opcode;
    opcode = PREG->u.o.opcw;
    goto op_switch;

  nextop:

    old_op = opcode;
    opcode = PREG->opc;

  op_switch:

#ifdef ANALYST
    Yap_opcount[opcode]++;
    Yap_2opcount[old_op][opcode]++;
#ifdef DEBUG_XX
    ops_done++;
    /*    if (B->cp_b > 0x103fff90)
      fprintf(stderr,"(%ld) doing %s, done %s, B is %p, HB is %p, H is %p\n",
      ops_done,Yap_op_names[opcode],Yap_op_names[old_op],B,B->cp_h,H);*/
#endif
#endif /* ANALYST */

    switch (opcode) {
#endif /* USE_THREADED_CODE */

    noheapleft:
      saveregs();
      if (!Yap_growheap(FALSE, 0, NULL)) {
      Yap_Error(OUT_OF_HEAP_ERROR, TermNil, "YAP failed to grow heap: %s", Yap_ErrorMessage);
      setregs();
      FAIL();
      }
      setregs();
      CACHE_A1();
      goto reset_absmi;

#if !OS_HANDLES_TR_OVERFLOW
    notrailleft:
      /* if we are within indexing code, the system may have to
       * update a S */
#if SHADOW_S
      S = SREG;
#endif
      /* YREG =was pointing to where we were going to build the
       * next choice-point. The stack shifter will need to know this
       * to move the local stack */
      if (YREG > (CELL *) PROTECT_FROZEN_B(B)) {
      ASP = (CELL *) PROTECT_FROZEN_B(B);
      } else {
      ASP = YREG+E_CB;
      }
      saveregs();
      if(!Yap_growtrail (sizeof(CELL) * 16 * 1024L, FALSE)) {
      Yap_Error(OUT_OF_TRAIL_ERROR,TermNil,"YAP failed to reserve %ld bytes in growtrail",sizeof(CELL) * 16 * 1024L);
      setregs();
      FAIL();
      }
      setregs();
      goto reset_absmi;

#endif /* OS_HANDLES_TR_OVERFLOW */

      BOp(Ystop, l);
      if (YREG > (CELL *) PROTECT_FROZEN_B(B)) {
      ASP = (CELL *) PROTECT_FROZEN_B(B);
      }
      else {
      ASP = YREG;
      }
      Yap_StartSlots();
      saveregs();
#if PUSH_REGS
      restore_absmi_regs(old_regs);
#endif
#if BP_FREE
      P1REG = PCBACKUP;
#endif
      return 1;
      ENDBOp();

      BOp(Nstop, e);
      if (YREG > (CELL *) PROTECT_FROZEN_B(B)) {
      ASP = (CELL *) PROTECT_FROZEN_B(B);
      }
      else {
      ASP = YREG;
      }
      Yap_StartSlots();
      saveregs();
#if PUSH_REGS
      restore_absmi_regs(old_regs);
#endif
#if BP_FREE
      P1REG = PCBACKUP;
#endif
      return (0);
      ENDBOp();

/*****************************************************************
*        Plain try - retry - trust instructions                  *
*****************************************************************/
      /* try_me    Label,NArgs */
      Op(try_me, ld);
      /* check if enough space between trail and codespace */
      check_trail(TR);
      /* I use YREG =to go through the choicepoint. Usually YREG =is in a
       * register, but sometimes (X86) not. In this case, have a
       * new register to point at YREG =*/
      CACHE_Y(YREG);
      /* store arguments for procedure */
      store_at_least_one_arg(PREG->u.ld.s);
      /* store abstract machine registers */
      store_yaam_regs(PREG->u.ld.d, 0);
      /* On a try_me, set cut to point at previous choicepoint,
       * that is, to the B before the cut.
       */
      set_cut(S_YREG, B);
      /* now, install the new YREG =*/
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      PREG = NEXTOP(PREG, ld);
      GONext();
      ENDOp();

      /* retry_me    Label,NArgs */
      Op(retry_me, ld);
      CACHE_Y(B);
      /* After retry, cut should be pointing at the parent
       * choicepoint for the current B */
      restore_yaam_regs(PREG->u.ld.d);
      restore_at_least_one_arg(PREG->u.ld.s);
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      PREG = NEXTOP(PREG, ld);
      GONext();
      ENDOp();

      /* trust_me    UnusedLabel,NArgs */
      Op(trust_me, ld);
      CACHE_Y(B);
#ifdef YAPOR
      if (SCH_top_shared_cp(B)) {
      SCH_last_alternative(PREG, B_YREG);
      restore_at_least_one_arg(PREG->u.ld.s);
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B->cp_b);
      }
      else
#endif      /* YAPOR */
      {
      pop_yaam_regs();
      pop_at_least_one_arg(PREG->u.ld.s);
      /* After trust, cut should be pointing at the new top
       * choicepoint */
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B);
      }
      PREG = NEXTOP(PREG, ld);
      SET_BB(B_YREG);
      ENDCACHE_Y();
      GONext();
      ENDOp();

/*****************************************************************
*        Profiled try - retry - trust instructions               *
*****************************************************************/

      /* profiled_enter_me    Pred */
      Op(enter_profiling, p);
      LOCK(PREG->u.p.p->StatisticsForPred.lock);
      PREG->u.p.p->StatisticsForPred.NOfEntries++;
      UNLOCK(PREG->u.p.p->StatisticsForPred.lock);
      PREG = NEXTOP(PREG, p);
      GONext();
      ENDOp();

      /* profiled_enter     */
      Op(enter_a_profiling, e);
      {
      PredEntry *pen = RepPredProp((Prop)IntegerOfTerm(ENV[-EnvSizeInCells-2]));
      PREG = NEXTOP(PREG, e);
      LOCK(pen->StatisticsForPred.lock);
      pen->StatisticsForPred.NOfEntries++;
      UNLOCK(pen->StatisticsForPred.lock);
      }
      GONext();
      ENDOp();

      /* profiled_retry    Label,NArgs */
      Op(retry_profiled, p);
      LOCK(PREG->u.p.p->StatisticsForPred.lock);
      PREG->u.p.p->StatisticsForPred.NOfRetries++;
      UNLOCK(PREG->u.p.p->StatisticsForPred.lock);
      PREG = NEXTOP(PREG, p);
      GONext();
      ENDOp();

      /* profiled_retry_me    Label,NArgs */
      Op(profiled_retry_me, ld);
      CACHE_Y(B);
      /* After retry, cut should be pointing at the parent
       * choicepoint for the current B */
      LOCK(PREG->u.ld.p->StatisticsForPred.lock);
      PREG->u.ld.p->StatisticsForPred.NOfRetries++;
      UNLOCK(PREG->u.ld.p->StatisticsForPred.lock);
      restore_yaam_regs(PREG->u.ld.d);
      restore_args(PREG->u.ld.s);
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      PREG = NEXTOP(PREG, ld);
      GONext();
      ENDOp();

      /* profiled_trust_me    UnusedLabel,NArgs */
      Op(profiled_trust_me, ld);
      CACHE_Y(B);
#ifdef YAPOR
      if (SCH_top_shared_cp(B)) {
      SCH_last_alternative(PREG, B_YREG);
      restore_args(PREG->u.ld.s);
#ifdef FROZEN_STACKS
        S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B->cp_b);
      }
      else
#endif      /* YAPOR */
      {
      pop_yaam_regs();
      pop_args(PREG->u.ld.s);
      /* After trust, cut should be pointing at the new top
       * choicepoint */
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B);
      }
      SET_BB(B_YREG);
      ENDCACHE_Y();
      LOCK(PREG->u.ld.p->StatisticsForPred.lock);
      PREG->u.ld.p->StatisticsForPred.NOfRetries++;
      UNLOCK(PREG->u.ld.p->StatisticsForPred.lock);
      PREG = NEXTOP(PREG, ld);
      GONext();
      ENDOp();

/*****************************************************************
*        Call count instructions                                 *
*****************************************************************/

      /* count_enter_me    Label,NArgs */
      Op(count_call, p);
      LOCK(PREG->u.p.p->StatisticsForPred.lock);
      PREG->u.p.p->StatisticsForPred.NOfEntries++;
      UNLOCK(PREG->u.p.p->StatisticsForPred.lock);
      ReductionsCounter--;
      if (ReductionsCounter == 0 && ReductionsCounterOn) {
      saveregs();
      Yap_Error(CALL_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      PredEntriesCounter--;
      if (PredEntriesCounter == 0 && PredEntriesCounterOn) {
      saveregs();
      Yap_Error(PRED_ENTRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      PREG = NEXTOP(PREG, p);
      GONext();
      ENDOp();

      /* count_enter_me    Label,NArgs */
      Op(count_a_call, e);
      {
      PredEntry *pen = RepPredProp((Prop)IntegerOfTerm(ENV[-EnvSizeInCells-2]));
      PREG = NEXTOP(PREG, e);
      LOCK(pen->StatisticsForPred.lock);
      pen->StatisticsForPred.NOfEntries++;
      UNLOCK(pen->StatisticsForPred.lock);
      ReductionsCounter--;
      if (ReductionsCounter == 0 && ReductionsCounterOn) {
        saveregs();
        Yap_Error(CALL_COUNTER_UNDERFLOW,TermNil,"");
        setregs();
        JMPNext();
      } 
      PredEntriesCounter--;
      if (PredEntriesCounter == 0 && PredEntriesCounterOn) {
        saveregs();
        Yap_Error(PRED_ENTRY_COUNTER_UNDERFLOW,TermNil,"");
        setregs();
        JMPNext();
      } 
      }
      GONext();
      ENDOp();

      /* count_retry    Label,NArgs */
      Op(count_retry, p);
      LOCK(PREG->u.p.p->StatisticsForPred.lock);
      PREG->u.p.p->StatisticsForPred.NOfRetries++;
      UNLOCK(PREG->u.p.p->StatisticsForPred.lock);
      RetriesCounter--;
      if (RetriesCounter == 0 && RetriesCounterOn) {
      saveregs();
      Yap_Error(RETRY_COUNTER_UNDERFLOW,TermNil,"");
      JMPNext();
      setregs();
      } 
      PredEntriesCounter--;
      if (PredEntriesCounter == 0 && PredEntriesCounterOn) {
      saveregs();
      Yap_Error(PRED_ENTRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      PREG = NEXTOP(PREG, p);
      GONext();
      ENDOp();

      /* count_retry_me    Label,NArgs */
      Op(count_retry_me, ld);
      CACHE_Y(B);
      /* After retry, cut should be pointing at the parent
       * choicepoint for the current B */
      LOCK(((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.lock);
      ((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.NOfRetries++;
      UNLOCK(((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.lock);
      RetriesCounter--;
      if (RetriesCounter == 0 && RetriesCounterOn) {
      saveregs();
      Yap_Error(RETRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      PredEntriesCounter--;
      if (PredEntriesCounter == 0 && PredEntriesCounterOn) {
      saveregs();
      Yap_Error(PRED_ENTRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      restore_yaam_regs(PREG->u.ld.d);
      restore_args(PREG->u.ld.s);
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      PREG = NEXTOP(PREG, ld);
      GONext();
      ENDOp();

      /* count_trust_me    UnusedLabel,NArgs */
      Op(count_trust_me, ld);
      CACHE_Y(B);
#ifdef YAPOR
      if (SCH_top_shared_cp(B)) {
      SCH_last_alternative(PREG, B_YREG);
      restore_args(PREG->u.ld.s);
#ifdef FROZEN_STACKS
        S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B->cp_b);
      }
      else
#endif      /* YAPOR */
      {
      pop_yaam_regs();
      pop_args(PREG->u.ld.s);
      /* After trust, cut should be pointing at the new top
       * choicepoint */
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B);
      }
      SET_BB(B_YREG);
      ENDCACHE_Y();
      RetriesCounter--;
      if (RetriesCounter == 0) {
      saveregs();
      Yap_Error(RETRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      PredEntriesCounter--;
      if (PredEntriesCounter == 0) {
      saveregs();
      Yap_Error(PRED_ENTRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      LOCK(((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.lock);
      ((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.NOfRetries++;
      UNLOCK(((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.lock);
      PREG = NEXTOP(PREG, ld);
      GONext();
      ENDOp();

/*****************************************************************
*        enter a logical semantics dynamic predicate             *
*****************************************************************/

      /* only meaningful with THREADS on! */
      /* lock logical updates predicate.  */
      Op(lock_lu, p);
#if defined(YAPOR) || defined(THREADS)
      PP = PREG->u.p.p;
      READ_LOCK(PP->PRWLock);
      if (PP->cs.p_code.TrueCodeOfPred != PREG) {
      PREG = PP->cs.p_code.TrueCodeOfPred;
      READ_UNLOCK(PP->PRWLock);
      PP = NULL;
      GONext();
      }
#endif
      PREG = NEXTOP(PREG, p);
      GONext();
      ENDOp();
 
      /* only meaningful with THREADS on! */
      /* lock logical updates predicate.  */
      Op(unlock_lu, e);
      PREG = NEXTOP(PREG, e);
#if defined(YAPOR) || defined(THREADS)
      if (PP) {
      READ_UNLOCK(PP->PRWLock);
      PP = NULL;
      }
#endif
      GONext();
      ENDOp();
 

      /* enter logical pred               */
      BOp(stale_lu_index, Ill);
      {
      yamop *ipc;
#if defined(YAPOR) || defined(THREADS)
      PredEntry *pe = PREG->u.Ill.p;
#endif

      /* update ASP before calling IPred */
      ASP = YREG+E_CB;
      if (ASP > (CELL *) PROTECT_FROZEN_B(B)) {
        ASP = (CELL *) PROTECT_FROZEN_B(B);
      }
      saveregs();
#if defined(YAPOR) || defined(THREADS)
      LOCK(pe->PELock);
      if (PP) {
        /* PP would be NULL for local preds */
        READ_UNLOCK(PP->PRWLock);
        PP = NULL;
      }
      if (!same_lu_block(PREG_ADDR, PREG)) {
        PREG = *PREG_ADDR;
        UNLOCK(pe->PELock);
        JMPNext();
      }
#endif
      ipc = Yap_CleanUpIndex(PREG->u.Ill.I);
      setregs();
      UNLOCK(pe->PELock);
      /* restart index */
      if (ipc == NULL) FAIL();
      PREG = ipc;
      save_pc();
      CACHE_A1();
      JMPNext();
      }
      ENDBOp();


      /* enter logical pred               */
      BOp(enter_lu_pred, Ill);
      /* mark the indexing code */
      {
      LogUpdIndex *cl = PREG->u.Ill.I;
      PREG = PREG->u.Ill.l1;
      LOCK(cl->ClLock);
      /* indicate the indexing code is being used */
#if defined(YAPOR) || defined(THREADS)
      /* just store a reference */
      INC_CLREF_COUNT(cl);
      TRAIL_CLREF(cl);
#else
      if (!(cl->ClFlags & InUseMask)) {
        cl->ClFlags |= InUseMask;
        TRAIL_CLREF(cl);
      }
#endif
      UNLOCK(cl->ClLock);
#if defined(YAPOR) || defined(THREADS)
      if (PP) {
        /* PP would be NULL for local preds */
        READ_UNLOCK(PP->PRWLock);
        PP = NULL;
      }
#endif
      }
      GONext();
      ENDBOp();

      /* trust a logical pred, that is, release the code     */
      BOp(trust_logical_pred, l);
      /* unmark the indexing code */
      /* mark the indexing code */
      {
      LogUpdIndex *cl = (LogUpdIndex *)PREG->u.l.l;
      PREG = NEXTOP(PREG, l);
      /* check if we are the ones using this code */
#if defined(YAPOR) || defined(THREADS)
      LOCK(cl->ClLock);
      DEC_CLREF_COUNT(cl);
      /* clear the entry from the trail */
      TR = --(B->cp_tr);
      /* actually get rid of the code */
      if (cl->ClRefCount == 0 && cl->ClFlags & ErasedMask) {
        yamop *next = PREG->u.ld.d;
        UNLOCK(cl->ClLock);
        if (next != FAILCODE) {
          LogUpdClause *lcl = ClauseCodeToLogUpdClause(next);
          /* I am the last one using this clause, hence I don't need a lock
             to dispose of it 
          */
          LOCK(lcl->ClLock);
          if (lcl->ClRefCount == 1) {
            /* make sure the clause isn't destroyed */
            /* always add an extra reference */
            INC_CLREF_COUNT(lcl);
            TRAIL_CLREF(lcl);
          }
          UNLOCK(lcl->ClLock);
        }
        PREG = Yap_ErLogUpdIndex(cl, PREG);
        save_pc();
      } else {
        UNLOCK(cl->ClLock);
      }
#else
      if (TrailTerm(B->cp_tr-1) == CLREF_TO_TRENTRY(cl) &&
          B->cp_tr != B->cp_b->cp_tr) {
        cl->ClFlags &= ~InUseMask;
        TR = --B->cp_tr;
        /* next, recover space for the indexing code if it was erased */
        if (cl->ClFlags & ErasedMask) {
          yamop *next = PREG->u.ld.d;
          if (next != FAILCODE) {
            LogUpdClause *lcl = ClauseCodeToLogUpdClause(next);
            /* make sure we don't erase the clause we are jumping too */
            if (lcl->ClRefCount == 1 && !(lcl->ClFlags & InUseMask)) {
            lcl->ClFlags |= InUseMask;
            TRAIL_CLREF(lcl);
            }
          }
          PREG = Yap_ErLogUpdIndex(cl, PREG);
          save_pc();
        }
      }
#endif
      }
      GONext();
      ENDBOp();

      /* enter logical pred               */
      BOp(alloc_for_logical_pred, EC);
      /* say that an environment is using this clause */
      /* we have our own copy for the clause */
#if defined(YAPOR) || defined(THREADS)
      {
      LogUpdClause *cl = PREG->u.EC.ClBase;

      LOCK(cl->ClLock);
      /* always add an extra reference */
      INC_CLREF_COUNT(cl);
      TRAIL_CLREF(cl);
      UNLOCK(cl->ClLock);
      if (PP) {
        READ_UNLOCK(PP->PRWLock);
        PP = NULL;
      }
      }
#else
      {
      LogUpdClause *cl = (LogUpdClause *)PREG->u.EC.ClBase;
      if (!(cl->ClFlags & InUseMask)) {
        /* Clause *cl = (Clause *)PREG->u.EC.ClBase;

        PREG->u.EC.ClTrail = TR-(tr_fr_ptr)Yap_TrailBase;
        PREG->u.EC.ClENV = LCL0-YENV;*/
        cl->ClFlags |= InUseMask;
        TRAIL_CLREF(cl);
      }
      }
#endif
      PREG = NEXTOP(PREG, EC);
      GONext();
      ENDBOp();

      /* copy database term               */
      BOp(copy_idb_term, e);
      {
      LogUpdClause *cl = ClauseCodeToLogUpdClause(PREG);
      Term t;

      ASP = YREG;
      saveregs();
      while ((t = Yap_FetchTermFromDB(cl->ClSource)) == 0L) {
        if (Yap_Error_TYPE == OUT_OF_ATTVARS_ERROR) {
          Yap_Error_TYPE = YAP_NO_ERROR;
          if (!Yap_growglobal(NULL)) {
            Yap_Error(OUT_OF_ATTVARS_ERROR, TermNil, Yap_ErrorMessage);
            FAIL();
          }
        } else {
          Yap_Error_TYPE = YAP_NO_ERROR;
          if (!Yap_gc(3, ENV, CP)) {
            Yap_Error(OUT_OF_STACK_ERROR, TermNil, Yap_ErrorMessage);
            FAIL();
          }
        }
      }
      if (!Yap_IUnify(ARG2, t)) {
        setregs();
        FAIL();
      }
      if (!Yap_IUnify(ARG3, MkDBRefTerm((DBRef)cl))) {
        setregs();
        FAIL();
      }
      setregs();

#if defined(YAPOR) || defined(THREADS)
      LOCK(cl->ClLock);
      /* always add an extra reference */
      INC_CLREF_COUNT(cl);
      TRAIL_CLREF(cl);
      UNLOCK(cl->ClLock);
      if (PP) {
        READ_UNLOCK(PP->PRWLock);
        PP = NULL;
      }
#else
      if (!(cl->ClFlags & InUseMask)) {
        /* Clause *cl = (Clause *)PREG->u.EC.ClBase;

        PREG->u.EC.ClTrail = TR-(tr_fr_ptr)Yap_TrailBase;
        PREG->u.EC.ClENV = LCL0-YENV;*/
        cl->ClFlags |= InUseMask;
        TRAIL_CLREF(cl);
      }
#endif
      }
      PREG = CPREG;
      YREG = ENV;
#ifdef DEPTH_LIMIT
      DEPTH = YREG[E_DEPTH];
#endif
      GONext();
      ENDBOp();


      /* unify with database term               */
      BOp(unify_idb_term, e);
      {
      LogUpdClause *cl = ClauseCodeToLogUpdClause(PREG);

      saveregs();
      if (!Yap_IUnify(ARG2, cl->ClSource->Entry)) {
        setregs();
        FAIL();
      }
      if (!Yap_IUnify(ARG3, MkDBRefTerm((DBRef)cl))) {
        setregs();
        FAIL();
      }
      setregs();

      /* say that an environment is using this clause */
      /* we have our own copy for the clause */
#if defined(YAPOR) || defined(THREADS)
      LOCK(cl->ClLock);
      /* always add an extra reference */
      INC_CLREF_COUNT(cl);
      TRAIL_CLREF(cl);
      UNLOCK(cl->ClLock);
      if (PP) {
        READ_UNLOCK(PP->PRWLock);
        PP = NULL;
      }
#else
      if (!(cl->ClFlags & InUseMask)) {
        /* Clause *cl = (Clause *)PREG->u.EC.ClBase;

        PREG->u.EC.ClTrail = TR-(tr_fr_ptr)Yap_TrailBase;
        PREG->u.EC.ClENV = LCL0-YENV;*/
        cl->ClFlags |= InUseMask;
        TRAIL_CLREF(cl);
      }
#endif
      }
      PREG = CPREG;
      YREG = ENV;
#ifdef DEPTH_LIMIT
      DEPTH = YREG[E_DEPTH];
#endif
      GONext();
      ENDBOp();





/*****************************************************************
*        try and retry of dynamic predicates                     *
*****************************************************************/

      /* spy_or_trymark                   */
      BOp(spy_or_trymark, ld);
      READ_LOCK(((PredEntry *)(PREG->u.ld.p))->PRWLock);
      PREG = (yamop *)(&(((PredEntry *)(PREG->u.ld.p))->OpcodeOfPred));
      READ_UNLOCK(((PredEntry *)(PREG->u.ld.p))->PRWLock);
      goto dospy;
      ENDBOp();

      /* try_and_mark   Label,NArgs       */
      BOp(try_and_mark, ld);
      check_trail(TR);
#if defined(YAPOR) || defined(THREADS)
#ifdef YAPOR
      /* The flags I check here should never change during execution */
      CUT_wait_leftmost();
#endif /* YAPOR */
      READ_LOCK(((PredEntry *)(PREG->u.ld.p))->PRWLock);
      if (PREG->u.ld.p->CodeOfPred != PREG) {
      /* oops, someone changed the procedure under our feet,
         fortunately this is no big deal because we haven't done
         anything yet */
      READ_UNLOCK(((PredEntry *)(PREG->u.ld.p))->PRWLock);
      PREG = PREG->u.ld.p->CodeOfPred;
      /* for profiler */
      save_pc();
      JMPNext();
      }
#endif
      CACHE_Y(YREG);
      PREG = PREG->u.ld.d;
      /*
      I've got a read lock on the DB, so I don't need to care...
       niaaahh.... niahhhh...
      */
      LOCK(DynamicLock(PREG));
      /* one can now mess around with the predicate */
      READ_UNLOCK(((PredEntry *)(PREG->u.ld.p))->PRWLock);
      BEGD(d1);
      d1 = PREG->u.ld.s;
      store_args(d1);
      store_yaam_regs(PREG, 0);
      ENDD(d1);
      set_cut(S_YREG, B);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();
#if defined(YAPOR) || defined(THREADS)
      INC_CLREF_COUNT(ClauseCodeToDynamicClause(PREG));
      UNLOCK(DynamicLock(PREG));
      TRAIL_CLREF(ClauseCodeToDynamicClause(PREG));
#else
      if (FlagOff(InUseMask, DynamicFlags(PREG))) {

      SetFlag(InUseMask, DynamicFlags(PREG));
      TRAIL_CLREF(ClauseCodeToDynamicClause(PREG));
      }
#endif
      PREG = NEXTOP(PREG,ld);
      JMPNext();

      ENDBOp();

      BOp(count_retry_and_mark, ld);
      RetriesCounter--;
      if (RetriesCounter == 0) {
      saveregs();
      Yap_Error(RETRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      PredEntriesCounter--;
      if (PredEntriesCounter == 0) {
      saveregs();
      Yap_Error(PRED_ENTRY_COUNTER_UNDERFLOW,TermNil,"");
      setregs();
      JMPNext();
      } 
      /* enter a retry dynamic */
      ENDBOp();

      BOp(profiled_retry_and_mark, ld);
      LOCK(((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.lock);
      ((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.NOfRetries++;
      UNLOCK(((PredEntry *)(PREG->u.ld.p))->StatisticsForPred.lock);
      /* enter a retry dynamic */
      ENDBOp();

      /* retry_and_mark   Label,NArgs     */
      BOp(retry_and_mark, ld);
#ifdef YAPOR
      CUT_wait_leftmost();
#endif /* YAPOR */
      /* need to make the DB stable until I get the new clause */
      READ_LOCK(PREG->u.ld.p->PRWLock);
      CACHE_Y(B);
      PREG = PREG->u.ld.d;
      LOCK(DynamicLock(PREG));
      READ_UNLOCK(PREG->u.ld.p->PRWLock);
      restore_yaam_regs(PREG);
      restore_args(PREG->u.ld.s);
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
#if defined(YAPOR) || defined(THREADS)
      INC_CLREF_COUNT(ClauseCodeToDynamicClause(PREG));
      TRAIL_CLREF(ClauseCodeToDynamicClause(PREG));
      UNLOCK(DynamicLock(PREG));
#else
      if (FlagOff(InUseMask, DynamicFlags(PREG))) {

      SetFlag(InUseMask, DynamicFlags(PREG));
      TRAIL_CLREF(ClauseCodeToDynamicClause(PREG));
      }
#endif
      PREG = NEXTOP(PREG,ld);
      JMPNext();

      ENDBOp();

/*****************************************************************
*        Failure                                                 *
*****************************************************************/

      /* trust_fail                       */
      BOp(trust_fail, e);
#ifdef CUT_C
      {
      while (POP_CHOICE_POINT(B->cp_b))
        { 
          POP_EXECUTE();
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      {
      choiceptr cut_pt;
      cut_pt = B->cp_b;
      CUT_prune_to(cut_pt);
      B = cut_pt;
      }
#else
      B = B->cp_b;
#endif      /* YAPOR */
      goto fail;
      ENDBOp();

#ifdef YAPOR
    shared_fail:
      B = LOCAL_top_cp;
      SET_BB(PROTECT_FROZEN_B(B));
      goto fail;
#endif      /* YAPOR */

      /* fail                             */
      PBOp(op_fail, e);

    fail:
      {
      register tr_fr_ptr pt0 = TR;
#if defined(YAPOR) || defined(THREADS)
      if (PP) {
        READ_UNLOCK(PP->PRWLock);
        PP = NULL;
      }
#endif
      PREG = B->cp_ap;
      save_pc();
      CACHE_TR(B->cp_tr);
      PREFETCH_OP(PREG);
      failloop:
      if (pt0 == S_TR) {
        SP = SP0;
#ifdef LOW_LEVEL_TRACER
        if (Yap_do_low_level_trace) {
          int go_on = TRUE;
          yamop *ipc = PREG;

          while (go_on) {
            op_numbers opnum = Yap_op_from_opcode(ipc->opc);

            go_on = FALSE;
            switch (opnum) {
#ifdef TABLING
            case _table_load_answer:
            low_level_trace(retry_table_loader, LOAD_CP(B)->cp_pred_entry, NULL);
            break;
            case _table_try_answer:
            case _table_retry_me:
            case _table_trust_me:
            case _table_retry:
            case _table_trust:
            case _table_completion:
            low_level_trace(retry_table_generator, GEN_CP(B)->cp_pred_entry, (CELL *)(GEN_CP(B) + 1));
            break;
            case _table_answer_resolution:
            low_level_trace(retry_table_consumer, CONS_CP(B)->cp_pred_entry, NULL);
            break;
            case _trie_retry_null:
            case _trie_trust_null:
            case _trie_retry_var:
            case _trie_trust_var:
            case _trie_retry_val:
            case _trie_trust_val:
            case _trie_retry_atom:
            case _trie_trust_atom:
            case _trie_retry_list:
            case _trie_trust_list:
            case _trie_retry_struct:
            case _trie_trust_struct:
            case _trie_retry_extension:
            case _trie_trust_extension:
            case _trie_retry_float:
            case _trie_trust_float:
            case _trie_retry_long:
            case _trie_trust_long:
            low_level_trace(retry_table_loader, UndefCode, NULL);
            break;
#endif /* TABLING */
            case _or_else:
            case _or_last:
            low_level_trace(retry_or, (PredEntry *)ipc, &(B->cp_a1));
            break;
            case _retry2:
            case _retry3:
            case _retry4:
            case _trust_logical_pred:
            ipc = NEXTOP(ipc,l);
            go_on = TRUE;
            break;
            case _jump:
            ipc = ipc->u.l.l;
            go_on = TRUE;
            break;
            case _retry_c:
            case _retry_userc:
            low_level_trace(retry_pred, ipc->u.lds.p, B->cp_args);
            break;
            case _retry_profiled:
            case _count_retry:
            ipc = NEXTOP(ipc,p);
            go_on = TRUE;
            break;
            case _retry_me:
            case _trust_me:
            case _count_retry_me:
            case _count_trust_me:
            case _profiled_retry_me:
            case _profiled_trust_me:
            case _retry_and_mark:
            case _profiled_retry_and_mark:
            case _retry:
            case _trust:
            low_level_trace(retry_pred, ipc->u.ld.p, B->cp_args);
            break;
            case _Nstop:
            case _Ystop:
            low_level_trace(retry_pred, NULL, B->cp_args);
            break;
            default:
            break;
            }
          }
        }
#endif      /* LOW_LEVEL_TRACER */
#ifdef FROZEN_STACKS
#ifdef SBA
        if (pt0 < TR_FZ || pt0 > (tr_fr_ptr)Yap_TrailTop)
#else
        if (pt0 < TR_FZ)
#endif /* SBA */
          {
            TR = TR_FZ;
            TRAIL_LINK(pt0);
          } else
#endif /* FROZEN_STACKS */
        RESTORE_TR();
        GONext();
      }
      BEGD(d1);
      d1 = TrailTerm(pt0-1);
      pt0--;
      if (IsVarTerm(d1)) {
#if defined(SBA) && defined(YAPOR)
        /* clean up the trail when we backtrack */
        if (Unsigned((Int)(d1)-(Int)(H_FZ)) >
            Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
          RESET_VARIABLE(STACK_TO_SBA(d1));
        } else
#endif
          /* normal variable */
          RESET_VARIABLE(d1);
        goto failloop;
      }
      /* pointer to code space */
      /* or updatable variable */
#if defined(TERM_EXTENSIONS) || defined(FROZEN_STACKS) || defined(MULTI_ASSIGNMENT_VARIABLES)
      if (IsPairTerm(d1))
#endif /* TERM_EXTENSIONS || FROZEN_STACKS || MULTI_ASSIGNMENT_VARIABLES */
        {
          register CELL flags;
          CELL *pt1 = RepPair(d1);
#ifdef LIMIT_TABLING
          if ((ADDR) pt1 == Yap_TrailBase) {
            sg_fr_ptr sg_fr = (sg_fr_ptr) TrailVal(pt0);
            TrailTerm(pt0) = AbsPair((CELL *)(pt0 - 1));
            SgFr_state(sg_fr)--;  /* complete_in_use --> complete : compiled_in_use --> compiled */
            insert_into_global_sg_fr_list(sg_fr);
            goto failloop;
          }
#endif /* LIMIT_TABLING */
#ifdef FROZEN_STACKS  /* TRAIL */
            /* avoid frozen segments */
#ifdef SBA
          if ((ADDR) pt1 >= HeapTop)
#else
          if ((ADDR) pt1 >= Yap_TrailBase)
#endif /* SBA */
            {
            pt0 = (tr_fr_ptr) pt1;
            goto failloop;
          }
#endif /* FROZEN_STACKS */
          flags = *pt1;
#if defined(YAPOR) || defined(THREADS)
          if (FlagOn(DBClMask, flags)) {
            DBRef dbr = DBStructFlagsToDBStruct(pt1);
            int erase;

            LOCK(dbr->lock);
            DEC_DBREF_COUNT(dbr);
            erase = (dbr->Flags & ErasedMask) && (dbr->ref_count == 0);
            UNLOCK(dbr->lock);
            if (erase) {
            saveregs();
            Yap_ErDBE(dbr);
            setregs();
            }
          } else {
            if (flags & LogUpdMask) {
            if (flags & IndexMask) {
              LogUpdIndex *cl = ClauseFlagsToLogUpdIndex(pt1);
              int erase;

              LOCK(cl->ClLock);
              DEC_CLREF_COUNT(cl);
              erase = (cl->ClFlags & ErasedMask) && !(cl->ClRefCount);
              UNLOCK(cl->ClLock);
              if (erase) {
                saveregs();
                /* at this point, 
                   we are the only ones accessing the clause,
                   hence we don't need to have a lock it */
                Yap_ErLogUpdIndex(cl, NULL);
                setregs();
              }
            } else {
              LogUpdClause *cl = ClauseFlagsToLogUpdClause(pt1);
              int erase;

              LOCK(cl->ClLock);
              DEC_CLREF_COUNT(cl);
              erase = (cl->ClFlags & ErasedMask) && !(cl->ClRefCount);
              UNLOCK(cl->ClLock);
              if (erase) {
                saveregs();
                /* at this point, 
                   we are the only ones accessing the clause,
                   hence we don't need to have a lock it */
                Yap_ErLogUpdCl(cl);
                setregs();
              }
            }
            } else {
            DynamicClause *cl = ClauseFlagsToDynamicClause(pt1);
            int erase;

            LOCK(cl->ClLock);
            DEC_CLREF_COUNT(cl);
            erase = (cl->ClFlags & ErasedMask) && !(cl->ClRefCount);
            UNLOCK(cl->ClLock);
            if (erase) {
              saveregs();
              /* at this point, 
                 we are the only ones accessing the clause,
                 hence we don't need to have a lock it */
              Yap_ErCl(cl);
              setregs();
            }
            }
          }
#else
          ResetFlag(InUseMask, flags);
          *pt1 = flags;
          if (FlagOn(ErasedMask, flags)) {
            if (FlagOn(DBClMask, flags)) {
            saveregs();
            Yap_ErDBE(DBStructFlagsToDBStruct(pt1));
            setregs();
            } else {
            saveregs();
            if (flags & LogUpdMask) {
              if (flags & IndexMask) {
                Yap_ErLogUpdIndex(ClauseFlagsToLogUpdIndex(pt1), NULL);
              } else {
                Yap_ErLogUpdCl(ClauseFlagsToLogUpdClause(pt1));
              }
            } else {
              Yap_ErCl(ClauseFlagsToDynamicClause(pt1));
            }
            setregs();
            }
          }
#endif
          goto failloop;
        }
#ifdef MULTI_ASSIGNMENT_VARIABLES
      else /* if (IsApplTerm(d1)) */ {
        CELL *pt = RepAppl(d1);
        /* AbsAppl means */
        /* multi-assignment variable */
        /* so the next cell is the old value */ 
#ifdef FROZEN_STACKS
        pt[0] = TrailVal(pt0-1);
        pt0 -= 1;
#else
        pt[0] = TrailTerm(pt0-1);
        pt0 -= 2;
#endif /* FROZEN_STACKS */
        goto failloop;
      }
#endif
      ENDD(d1);
      ENDCACHE_TR();
      }
      ENDPBOp();



/************************************************************************\
*     Cut & Commit Instructions                             *
\************************************************************************/

      /* cut                              */
      Op(cut, e);
      PREG = NEXTOP(PREG, e);
      BEGD(d0);
      /* assume cut is always in stack */
      d0 = YREG[E_CB];
#ifdef CUT_C
      {
      if (SHOULD_CUT_UP_TO(B,(choiceptr) d0))
        {
          while (POP_CHOICE_POINT(d0))
            {
            POP_EXECUTE();
            }
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to((choiceptr) d0);
#endif /* YAPOR */
      if (SHOULD_CUT_UP_TO(B,(choiceptr) d0)) {
      /* cut ! */
      while (B->cp_b < (choiceptr)d0) {
        B = B->cp_b;
      }
#ifdef TABLING
      abolish_incomplete_subgoals(B);
#endif /* TABLING */
      trim_trail:
      HBREG = PROTECT_FROZEN_H(B->cp_b);
#ifdef FROZEN_STACKS
        {
        tr_fr_ptr pt0, pt1, pbase;
        pbase = B->cp_tr;
        pt0 = pt1 = TR - 1;
        while (pt1 >= pbase) {
          BEGD(d1);
          d1 = TrailTerm(pt1);
          if (IsVarTerm(d1)) {
            if (d1 < (CELL)HBREG || d1 > Unsigned(B->cp_b)) { 
            TrailTerm(pt0) = d1;
            TrailVal(pt0) = TrailVal(pt1);
            pt0--;
            }
            pt1--;
          } else if (IsPairTerm(d1)) {
            CELL *pt = RepPair(d1);
#ifdef LIMIT_TABLING
            if ((ADDR) pt == Yap_TrailBase) {
            sg_fr_ptr sg_fr = (sg_fr_ptr) TrailVal(pt1);
            SgFr_state(sg_fr)--;  /* complete_in_use --> complete : compiled_in_use --> compiled */
            insert_into_global_sg_fr_list(sg_fr);
            } else
#endif /* LIMIT_TABLING */
            if ((ADDR) pt >= Yap_TrailBase) {
            /* skip, this is a problem because we lose information,
                   namely active references */
            pt1 = (tr_fr_ptr)pt;
            } else if ((*pt & (LogUpdMask|IndexMask)) == (LogUpdMask|IndexMask)) {
            LogUpdIndex *cl = ClauseFlagsToLogUpdIndex(pt);
            int erase;

            LOCK(cl->ClLock);
            DEC_CLREF_COUNT(cl);
            cl->ClFlags &= ~InUseMask;
            erase = (cl->ClFlags & ErasedMask) && !(cl->ClRefCount);
            UNLOCK(cl->ClLock);
            if (erase) {
              /* at this point, we are the only ones accessing the clause,
                 hence we don't need to have a lock it */
              saveregs();
              Yap_ErLogUpdIndex(cl, NULL);
              setregs();
            }
            } else {
            TrailTerm(pt0) = d1;
            TrailVal(pt0) = TrailVal(pt1);
            pt0--;
            }
            pt1--;
          } else if (IsApplTerm(d1)) {
             if (IN_BETWEEN(HBREG,RepAppl(d1),B->cp_b)) {
             /* deterministic binding to multi-assignment variable */
             pt1 -= 2;
             } else {
             TrailVal(pt0) = TrailVal(pt1);
             TrailTerm(pt0) = d1;
             TrailVal(pt0-1) = TrailVal(pt1-1);
             TrailTerm(pt0-1) = TrailTerm(pt1-1);
             pt0 -= 2;
             pt1 -= 2;
             }
          } else {
            TrailTerm(pt0) = d1;
            TrailVal(pt0) = TrailVal(pt1);
            pt0--;
            pt1--;
          }
          ENDD(d1);                              
        }
        if (pt0 != pt1) {
          int size;
          pt0++;
          size = TR - pt0;
          memcpy(pbase, pt0, size * sizeof(struct trail_frame));
          TR = pbase + size;
        }
      }
#else
        {
        tr_fr_ptr pt1, pt0;
        pt1 = pt0 = B->cp_tr;
        while (pt1 != TR) {
          BEGD(d1);
          d1 = TrailTerm(pt1);
          if (IsVarTerm(d1)) {
            if (d1 < (CELL)HBREG || d1 > Unsigned(B->cp_b)) { 
#ifdef FROZEN_STACKS
            TrailVal(pt0) = TrailVal(pt1);
#endif /* FROZEN_STACKS */
            TrailTerm(pt0) = d1;
            pt0++;
            }     
            pt1++;
          } else if (IsApplTerm(d1)) {
             if (IN_BETWEEN(HBREG,RepAppl(d1),B->cp_b)) {
#ifdef FROZEN_STACKS
             pt1 += 2;
#else
             pt1 += 3;
#endif
             } else {
#ifdef FROZEN_STACKS
             TrailVal(pt0) = TrailVal(pt1);
             TrailTerm(pt0) = d1;
             TrailVal(pt0+1) = TrailVal(pt1+1);
             TrailTerm(pt0+1) = TrailTerm(pt1+1);
             pt0 += 2;
             pt1 += 2;
#else
             TrailTerm(pt0+1) = TrailTerm(pt1+1);
             TrailTerm(pt0) = TrailTerm(pt0+2) = d1;
             pt0 += 3;
             pt1 += 3;
#endif /* FROZEN_STACKS */
             }
          } else if (IsPairTerm(d1)) {
            CELL *pt = RepPair(d1);
            if ((*pt & (LogUpdMask|IndexMask)) == (LogUpdMask|IndexMask)) {
            LogUpdIndex *cl = ClauseFlagsToLogUpdIndex(pt);
            int erase;

            LOCK(cl->ClLock);
            DEC_CLREF_COUNT(cl);
            cl->ClFlags &= ~InUseMask;
            erase = (cl->ClFlags & ErasedMask) && !(cl->ClRefCount);
            UNLOCK(cl->ClLock);
            if (erase) {
              /* at this point, we are the only ones accessing the clause,
                 hence we don't need to have a lock it */
              saveregs();
              Yap_ErLogUpdIndex(cl, NULL);
              setregs();
            }
            } else {
            TrailTerm(pt0) = d1;
            pt0++;
            }
            pt1++;
          } else {
            TrailTerm(pt0) = d1;
            pt0++;
            pt1++;
          }
          ENDD(d1);                              
        }
        TR = pt0;
      }
#endif /* FROZEN_STACKS */
      B = B->cp_b;
      SET_BB(PROTECT_FROZEN_B(B));
      }
      ENDD(d0);
      GONext();
      ENDOp();

      /* cut_t                            */
      /* cut_t does the same as cut */
      Op(cut_t, e);
      PREG = NEXTOP(PREG, e);
      BEGD(d0);
      /* assume cut is always in stack */
      d0 = YREG[E_CB];
#ifdef CUT_C
      {
      if (SHOULD_CUT_UP_TO(B,(choiceptr) d0))
        {
          while (POP_CHOICE_POINT(d0))
            {
            POP_EXECUTE();
            }
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to((choiceptr) d0);
#endif      /* YAPOR */
      if (SHOULD_CUT_UP_TO(B,(choiceptr) d0)) {
      /* cut ! */
      while (B->cp_b < (choiceptr)d0) {
        B = B->cp_b;
      }
#ifdef TABLING
      abolish_incomplete_subgoals(B);
#endif /* TABLING */
#ifdef FROZEN_STACKS
      { 
        choiceptr top_b = PROTECT_FROZEN_B(B->cp_b);
#ifdef SBA
        if (ENV > (CELL *) top_b || ENV < H) YREG = (CELL *) top_b;
#else
        if (ENV > (CELL *) top_b) YREG = (CELL *) top_b;
#endif /* SBA */
        else YREG = (CELL *)((CELL)ENV + ENV_Size(CPREG));
      }
#else
      if (ENV > (CELL *)B->cp_b) {
        YREG = (CELL *)B->cp_b;
      }
      else {
        YREG = (CELL *) ((CELL) ENV + ENV_Size(CPREG));
      }
#endif /* FROZEN_STACKS */
      YREG[E_CB] = d0;
      goto trim_trail;
      }
      ENDD(d0);
      GONext();
      ENDOp();

      /* cut_e                            */
      Op(cut_e, e);
      PREG = NEXTOP(PREG, e);
      BEGD(d0);
      /* we assume dealloc leaves in S the previous env             */
      d0 = SREG[E_CB];
#ifdef CUT_C
      {
      if (SHOULD_CUT_UP_TO(B,(choiceptr) d0))
        {
          while (POP_CHOICE_POINT(d0))
            {
            POP_EXECUTE();
            }
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to((choiceptr) d0);
#endif      /* YAPOR */
      if (SHOULD_CUT_UP_TO(B,(choiceptr)d0)) {
      /* cut ! */
      while (B->cp_b < (choiceptr)d0) {
        B = B->cp_b;
      }
#ifdef TABLING
      abolish_incomplete_subgoals(B);
#endif /* TABLING */
      goto trim_trail;
      }
      ENDD(d0);
      GONext();
      ENDOp();

      /* save_b_x      Xi                 */
      Op(save_b_x, x);
      BEGD(d0);
      d0 = PREG->u.x.x;
#if defined(SBA) && defined(FROZEN_STACKS)
      XREG(d0) = MkIntegerTerm((Int)B);
#else
      XREG(d0) = MkIntegerTerm(LCL0-(CELL *) (B));
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, x);
      ENDD(d0);
      GONext();
      ENDOp();

      /* save_b_y      Yi                 */
      Op(save_b_y, y);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.y.y,MkIntegerTerm((Int)B));
#else
      YREG[PREG->u.y.y] = MkIntegerTerm(LCL0-(CELL *) (B));
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, y);
      GONext();
      ENDOp();

      /* commit_b_x    Xi                 */
      Op(commit_b_x, x);
      BEGD(d0);
      d0 = XREG(PREG->u.x.x);
#ifdef COROUTINING
      CACHE_Y_AS_ENV(YREG);
      check_stack(NoStackCommitX, H);
      ENDCACHE_Y_AS_ENV();
    do_commit_b_x:
#endif
      /* skip a void call and a label */
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, x),sla),l);
      {
      choiceptr pt0;
#if defined(SBA) && defined(FROZEN_STACKS)
      pt0 = (choiceptr)IntegerOfTerm(d0);
#else
      pt0 = (choiceptr)(LCL0-IntegerOfTerm(d0));
#endif /* SBA && FROZEN_STACKS */
#ifdef CUT_C
      {
      if (SHOULD_CUT_UP_TO(B,(choiceptr) pt0))
        {
          while (POP_CHOICE_POINT(pt0))
            {
            POP_EXECUTE();
            }
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to(pt0);
#endif      /* YAPOR */
      if (SHOULD_CUT_UP_TO(B,pt0)) {
        while (B->cp_b < pt0) {
          B = B->cp_b;
        }
#ifdef TABLING
        abolish_incomplete_subgoals(B);
#endif /* TABLING */
        goto trim_trail;
      }
      }
      ENDD(d0);
      GONext();
      ENDOp();

      /* commit_b_y    Yi                 */
      Op(commit_b_y, y);
      BEGD(d0);
      d0 = YREG[PREG->u.y.y];
#ifdef COROUTINING
      CACHE_Y_AS_ENV(YREG);
      check_stack(NoStackCommitY, H);
      ENDCACHE_Y_AS_ENV();
    do_commit_b_y:
#endif
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, y),sla),l);
      {
      choiceptr pt0;
#if defined(SBA) && defined(FROZEN_STACKS)
      pt0 = (choiceptr)IntegerOfTerm(d0);
#else
      pt0 = (choiceptr)(LCL0-IntegerOfTerm(d0));
#endif /* SBA && FROZEN_STACKS */
#ifdef CUT_C
      {
        if (SHOULD_CUT_UP_TO(B,(choiceptr) pt0))
          {
            while (POP_CHOICE_POINT(pt0))
            {
              POP_EXECUTE();
            }
          }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to(pt0);
#endif      /* YAPOR */
      if (SHOULD_CUT_UP_TO(B,pt0)) {
        while (B->cp_b < pt0) {
          B = B->cp_b;
        }
#ifdef TABLING
        abolish_incomplete_subgoals(B);
#endif /* TABLING */
        goto trim_trail;
      }
      }
      ENDD(d0);
      GONext();
      ENDOp();

/*************************************************************************
*     Call / Proceed instructions                                      *
*************************************************************************/

/* Macros for stack trimming                                            */

      /* execute     Label               */
      BOp(execute, pp);
      {
      PredEntry *pt0;
      CACHE_Y_AS_ENV(YREG);
      pt0 = PREG->u.pp.p;
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
        low_level_trace(enter_pred,pt0,XREGS+1);
      }
#endif      /* LOW_LEVEL_TRACE */
      CACHE_A1();
      ALWAYS_LOOKAHEAD(pt0->OpcodeOfPred);
      BEGD(d0);
      d0 = (CELL)B;
#ifndef NO_CHECKING
      check_stack(NoStackExecute, H);
#endif
      PREG = pt0->CodeOfPred;
      /* for profiler */
      save_pc();
      ENV_YREG[E_CB] = d0;
      ENDD(d0);
#ifdef DEPTH_LIMIT
      if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is prolog */
        if (pt0->ModuleOfPred) {
          if (DEPTH == MkIntTerm(0))
            FAIL();
          else DEPTH = RESET_DEPTH();
        }
      } else if (pt0->ModuleOfPred)
        DEPTH -= MkIntConstant(2);
#endif      /* DEPTH_LIMIT */
      /* this is the equivalent to setting up the stack */
      ALWAYS_GONext();
      ALWAYS_END_PREFETCH();
      ENDCACHE_Y_AS_ENV();
      }
      ENDBOp();

    NoStackExecute:
      SREG = (CELL *) PREG->u.pp.p;
      if (ActiveSignals & YAP_CDOVF_SIGNAL) {
      ASP = YREG+E_CB;
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
        ASP = (CELL *)PROTECT_FROZEN_B(B);
      goto noheapleft;
      }
      if (ActiveSignals)
      goto creep;
      else
      goto NoStackExec;

      /* dexecute    Label               */
/* joint deallocate and execute */
      BOp(dexecute, pp);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,PREG->u.pp.p,XREGS+1);
#endif      /* LOW_LEVEL_TRACER */ 
     CACHE_Y_AS_ENV(YREG);
      {
      PredEntry *pt0;

      CACHE_A1();
      pt0 = PREG->u.pp.p;
#ifndef NO_CHECKING
      /* check stacks */
      check_stack(NoStackDExecute, H);
#endif
#ifdef DEPTH_LIMIT
      if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is primitives */
        if (pt0->ModuleOfPred) {
          if (DEPTH == MkIntTerm(0))
            FAIL();
          else DEPTH = RESET_DEPTH();
        }
      } else if (pt0->ModuleOfPred)
        DEPTH -= MkIntConstant(2);
#endif      /* DEPTH_LIMIT */
      PREG = pt0->CodeOfPred;
      /* for profiler */
      save_pc();
      ALWAYS_LOOKAHEAD(pt0->OpcodeOfPred);
      /* do deallocate */
      CPREG = (yamop *) ENV_YREG[E_CP];
      ENV_YREG = ENV = (CELL *) ENV_YREG[E_E];
#ifdef FROZEN_STACKS
      { 
        choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
        if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
        if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif /* SBA */
        else ENV_YREG = (CELL *)((CELL)ENV_YREG + ENV_Size(CPREG));
      }
#else
      if (ENV_YREG > (CELL *)B) {
        ENV_YREG = (CELL *)B;
      }
      else {
        ENV_YREG = (CELL *) ((CELL) ENV_YREG + ENV_Size(CPREG));
      }
#endif /* FROZEN_STACKS */
      WRITEBACK_Y_AS_ENV();
      /* setup GB */
      ENV_YREG[E_CB] = (CELL) B;
      ALWAYS_GONext();
      ALWAYS_END_PREFETCH();
      }
      ENDCACHE_Y_AS_ENV();
      ENDBOp();

      BOp(fcall, sla);
      CACHE_Y_AS_ENV(YREG);
      ENV_YREG[E_CP] = (CELL) CPREG;
      ENV_YREG[E_E] = (CELL) ENV;
#ifdef DEPTH_LIMIT
      ENV_YREG[E_DEPTH] = DEPTH;
#endif      /* DEPTH_LIMIT */
      ENDCACHE_Y_AS_ENV();
      ENDBOp();

      BOp(call, sla);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,PREG->u.sla.sla_u.p,XREGS+1);
#endif      /* LOW_LEVEL_TRACER */
      CACHE_Y_AS_ENV(YREG);
      {
      PredEntry *pt;
      pt = PREG->u.sla.sla_u.p;
      CACHE_A1();
#ifndef NO_CHECKING
      check_stack(NoStackCall, H);
#endif
      ENV = ENV_YREG;
      /* Try to preserve the environment */
      ENV_YREG = (CELL *) (((char *) ENV_YREG) + PREG->u.sla.s);
      CPREG = NEXTOP(PREG, sla);
      ALWAYS_LOOKAHEAD(pt->OpcodeOfPred);
      PREG = pt->CodeOfPred;
      /* for profiler */
      save_pc();
#ifdef DEPTH_LIMIT
      if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is primitives */
        if (pt->ModuleOfPred) {
          if (DEPTH == MkIntTerm(0))
            FAIL();
          else DEPTH = RESET_DEPTH();
        }
      } else if (pt->ModuleOfPred)
        DEPTH -= MkIntConstant(2);
#endif      /* DEPTH_LIMIT */
#ifdef FROZEN_STACKS
      { 
        choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
        if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
        if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif /* SBA */
      }
#else
      if (ENV_YREG > (CELL *) B) {
        ENV_YREG = (CELL *) B;
      }
#endif /* FROZEN_STACKS */
      WRITEBACK_Y_AS_ENV();
      /* setup GB */
      ENV_YREG[E_CB] = (CELL) B;
#ifdef YAPOR
      SCH_check_requests();
#endif      /* YAPOR */
      ALWAYS_GONext();
      ALWAYS_END_PREFETCH();
      }
      ENDCACHE_Y_AS_ENV();
      ENDBOp();

    NoStackCall:
      /* on X86 machines S will not actually be holding the pointer to pred */
      if (ActiveSignals & YAP_CREEP_SIGNAL) {
      PredEntry *ap = PREG->u.sla.sla_u.p;
      if (ap->PredFlags & HiddenPredFlag) {
        CACHE_Y_AS_ENV(YREG);
        CACHE_A1();
        ENV = ENV_YREG;
        /* Try to preserve the environment */
        ENV_YREG = (CELL *) (((char *) YREG) + PREG->u.sla.s);
        CPREG = NEXTOP(PREG, sla);
        ALWAYS_LOOKAHEAD(ap->OpcodeOfPred);
        PREG = ap->CodeOfPred;
        /* for profiler */
        save_pc();
        check_depth(DEPTH, ap);
#ifdef FROZEN_STACKS
        { 
          choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
          if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
          if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif
        }
#else
        if (ENV_YREG > (CELL *) B) {
          ENV_YREG = (CELL *) B;
        }
#endif /* FROZEN_STACKS */
        WRITEBACK_Y_AS_ENV();
        /* setup GB */
        ENV_YREG[E_CB] = (CELL) B;
#ifdef YAPOR
        SCH_check_requests();
#endif      /* YAPOR */
        ALWAYS_GONext();
        ALWAYS_END_PREFETCH();
        ENDCACHE_Y_AS_ENV();
      } else {
        SREG = (CELL *) ap;
        goto creepc;
      }
      }
      SREG = (CELL *) PREG->u.sla.sla_u.p;
      if (ActiveSignals & YAP_CDOVF_SIGNAL) {
      ASP = (CELL *) (((char *) YREG) + PREG->u.sla.s);
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
        ASP = (CELL *)PROTECT_FROZEN_B(B);
      goto noheapleft;
      }
      if (ActiveSignals) {
      goto creepc;
      }
      ASP = (CELL *) (((char *) YREG) + PREG->u.sla.s);
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
      ASP = (CELL *)PROTECT_FROZEN_B(B);
      saveregs();
      if (!Yap_gc(((PredEntry *)SREG)->ArityOfPE, YREG, NEXTOP(PREG, sla))) {
      Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs();

      JMPNext();


      /* don't forget I cannot creep at deallocate (where to?) */
      /* also, this is unusual in that I have already done deallocate,
       so I don't need to redo it.
       */ 
    NoStackDeallocate:
      if (ActiveSignals & YAP_CREEP_SIGNAL) {
      GONext();
      }
      ASP = YREG;
      /* cut_e */
      if (SREG <= ASP) {
      ASP = SREG-EnvSizeInCells;
      }
      if (ActiveSignals & YAP_CDOVF_SIGNAL) {
      goto noheapleft;
      }
      if (ActiveSignals) {
      if (Yap_op_from_opcode(PREG->opc) == _cut_e) {
        /* followed by a cut */
        ARG1 = MkIntegerTerm(LCL0-(CELL *)SREG[E_CB]);
        SREG = (CELL *)RepPredProp(Yap_GetPredPropByFunc(FunctorCutBy,1));
      } else {
        SREG = (CELL *)RepPredProp(Yap_GetPredPropByAtom(AtomTrue,0));
      }
      goto creep;
      }
      saveregs();
      if (!Yap_gc(0, ENV, CPREG)) {
      Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs();
      JMPNext();

#ifdef COROUTINING

     /* This is easier: I know there is an environment so I cannot do allocate */
    NoStackCommitY:
      /* find something to fool S */
      if (!ActiveSignals || ActiveSignals & YAP_CDOVF_SIGNAL) {
      goto do_commit_b_y;
      }
      if (!(ActiveSignals & YAP_CREEP_SIGNAL)) {
      SREG = (CELL *)RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(AtomRestoreRegs,2),0));
      XREGS[0] = YREG[PREG->u.y.y];
      PREG = NEXTOP(PREG,y);
      goto creep_either;
      }
      /* don't do debugging and friends here */
      goto do_commit_b_y;

      /* Problem: have I got an environment or not? */
    NoStackCommitX:
      /* find something to fool S */
      if (!ActiveSignals || ActiveSignals & YAP_CDOVF_SIGNAL) {
      goto do_commit_b_x;
      }
      if (!(ActiveSignals & YAP_CREEP_SIGNAL)) {
      SREG = (CELL *)RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(AtomRestoreRegs,2),0));
#if USE_THREADED_CODE
      if (PREG->opc == (OPCODE)OpAddress[_fcall])
#else
        if (PREG->opc == _fcall)
#endif
          {
            /* fill it up */
            CACHE_Y_AS_ENV(YREG);
            ENV_YREG[E_CP] = (CELL) CPREG;
            ENV_YREG[E_E] = (CELL) ENV;
#ifdef DEPTH_LIMIT
            ENV_YREG[E_DEPTH] = DEPTH;
#endif      /* DEPTH_LIMIT */
            ENDCACHE_Y_AS_ENV();
          }
      XREGS[0] = XREG(PREG->u.x.x);
      PREG = NEXTOP(PREG,x);
      goto creep_either;
      }
      /* don't do debugging and friends here */
      goto do_commit_b_x;

      /* don't forget I cannot creep at ; */
    NoStackEither:
      if (ActiveSignals & YAP_CREEP_SIGNAL) {
      goto either_notest;
      }
      /* find something to fool S */
      SREG = (CELL *)RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(AtomRestoreRegs,1),0));
      if (ActiveSignals & YAP_CDOVF_SIGNAL) {
      ASP = (CELL *) (((char *) YREG) + PREG->u.sla.s);
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
        ASP = (CELL *)PROTECT_FROZEN_B(B);
      goto noheapleft;
      }
      if (ActiveSignals) {
      goto creep_either;
      }
      ASP = (CELL *) (((char *) YREG) + PREG->u.sla.s);
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
      ASP = (CELL *)PROTECT_FROZEN_B(B);
      saveregs();
      if (!Yap_gc(0, YREG, NEXTOP(PREG, sla))) {
      Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs();
      JMPNext();

    creep_either:             /* do creep in either      */
      ENV = YREG;
      CPREG = NEXTOP(PREG, sla);
      YREG = (CELL *) (((char *) YREG) + PREG->u.sla.s);
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (YREG > (CELL *) top_b || YREG < H) YREG = (CELL *) top_b;
#else
      if (YREG > (CELL *) top_b) YREG = (CELL *) top_b;
#endif /* SBA */
      else YREG = YREG + ENV_Size(CPREG);
      }
#else
      if (YREG > (CELL *) B)
      YREG = (CELL *) B;
#endif /* FROZEN_STACKS */
      /* setup GB */
      ARG1 = push_live_regs(CPREG);
      /* ARG0 has an extra argument for suspended cuts */
      ARG2 = XREGS[0];
      YREG[E_CB] = (CELL) B;
      goto creep;
#endif

    creepc:             /* do creep in call                                     */
      ENV = YREG;
      CPREG = NEXTOP(PREG, sla);
      YREG = (CELL *) (((char *) YREG) + PREG->u.sla.s);
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (YREG > (CELL *) top_b || YREG < H) YREG = (CELL *) top_b;
#else
      if (YREG > (CELL *) top_b) YREG = (CELL *) top_b;
#endif /* SBA */
      else YREG = YREG + ENV_Size(CPREG);
      }
#else
      if (YREG > (CELL *) B)
      YREG = (CELL *) B;
      else
      /* I am not sure about this */
      YREG = YREG + ENV_Size(CPREG);
#endif /* FROZEN_STACKS */
      /* setup GB */
      YREG[E_CB] = (CELL) B;
      goto creep;

    NoStackDExecute:
      if (ActiveSignals & YAP_CREEP_SIGNAL) {
      PredEntry *ap = PREG->u.p.p;

      if (ap->PredFlags & HiddenPredFlag) {
        CACHE_Y_AS_ENV(YREG);
        CACHE_A1();
        check_depth(DEPTH, ap);
        PREG = ap->CodeOfPred;
        /* for profiler */
        save_pc();
        ALWAYS_LOOKAHEAD(ap->OpcodeOfPred);
        /* do deallocate */
        CPREG = (yamop *) ENV_YREG[E_CP];
        ENV_YREG = ENV = (CELL *) ENV_YREG[E_E];
#ifdef FROZEN_STACKS
        { 
          choiceptr top_b = PROTECT_FROZEN_B(B);

#ifdef SBA
          if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
          if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif
          else ENV_YREG = (CELL *)((CELL)ENV_YREG + ENV_Size(CPREG));
        }
#else
        if (ENV_YREG > (CELL *)B) {
          ENV_YREG = (CELL *)B;
        } else {
          ENV_YREG = (CELL *) ((CELL) ENV_YREG + ENV_Size(CPREG));
        }
#endif /* FROZEN_STACKS */
        WRITEBACK_Y_AS_ENV();
        /* setup GB */
        ENV_YREG[E_CB] = (CELL) B;
        ALWAYS_GONext();
        ALWAYS_END_PREFETCH();
        ENDCACHE_Y_AS_ENV();
      } else {
        SREG = (CELL *) ap;
        goto creepde;
      }
      }
      /* set SREG for next instructions */
      SREG = (CELL *) PREG->u.p.p;
      if (ActiveSignals & YAP_CDOVF_SIGNAL) {
      ASP = YREG+E_CB;
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
        ASP = (CELL *)PROTECT_FROZEN_B(B);
      goto noheapleft;
      }
      if (ActiveSignals)
      goto creepde;
      /* try performing garbage collection */

      ASP = YREG+E_CB;
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
      ASP = (CELL *)PROTECT_FROZEN_B(B);
      saveregs();
      if (!Yap_gc(((PredEntry *)(SREG))->ArityOfPE, (CELL *)YREG[E_E], (yamop *)YREG[E_CP])) {
      Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs();
      /* hopefully, gc will succeeded, and we will retry
       * the instruction */
      JMPNext();

    NoStackExec:

      /* try performing garbage collection */

      ASP = YREG+E_CB;
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
      ASP = (CELL *)PROTECT_FROZEN_B(B);
      saveregs();
      if (!Yap_gc(((PredEntry *)(SREG))->ArityOfPE, ENV, CPREG)) {
      Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs();
      /* hopefully, gc will succeeded, and we will retry
       * the instruction */
      JMPNext();

    creepde:
      /* first, deallocate */
      CPREG = (yamop *) YREG[E_CP];
      ENV = YREG = (CELL *) YREG[E_E];
#ifdef DEPTH_LIMIT
      YREG[E_DEPTH] = DEPTH;
#endif      /* DEPTH_LIMIT */
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (YREG > (CELL *) top_b || YREG < H) YREG = (CELL *) top_b;
#else
      if (YREG > (CELL *) top_b) YREG = (CELL *) top_b;
#endif /* SBA */
      else YREG = (CELL *) ((CELL)YREG + ENV_Size(CPREG));
      }
#else
      if (YREG > (CELL *) B) {
      YREG = (CELL *) B;
      }
      else {
      YREG = (CELL *) ((CELL) YREG + ENV_Size(CPREG));
      }
#endif /* FROZEN_STACKS */
      /* setup GB */
      YREG[E_CB] = (CELL) B;

      /* and now CREEP */

    creep:
#if  _MSC_VER || defined(__MINGW32__)
      /* I need this for Windows and other systems where SIGINT
         is not proceesed by same thread as absmi */
      LOCK(SignalLock);
      if (Yap_PrologMode & (AbortMode|InterruptMode)) {
      CreepFlag = CalculateStackGap();
      UNLOCK(SignalLock);
      /* same instruction */
      if (Yap_PrologMode & InterruptMode) {
        Yap_PrologMode &= ~InterruptMode;
        ASP = YREG+E_CB;
        if (ASP > (CELL *)PROTECT_FROZEN_B(B))
          ASP = (CELL *)PROTECT_FROZEN_B(B);
        saveregs();
        Yap_ProcessSIGINT();
        setregs();
      } 
      JMPNext();
      }
      UNLOCK(SignalLock);
#endif
#if SHADOW_S
      S = SREG;
#endif
      BEGD(d0);
      d0 = ((PredEntry *)(SREG))->ArityOfPE;
      if (d0 == 0) {
      H[1] = MkAtomTerm((Atom) ((PredEntry *)(SREG))->FunctorOfPred);
      }
      else {
      H[d0 + 2] = AbsAppl(H);
      *H = (CELL) ((PredEntry *)(SREG))->FunctorOfPred;
      H++;
      BEGP(pt1);
      pt1 = XREGS + 1;
      for (; d0 > 0; --d0) {
        BEGD(d1);
        BEGP(pt0);
        pt0 = pt1;
        d1 = *pt0;
        deref_head(d1, creep_unk);
      creep_nonvar:
        /* just copy it to the heap */
        pt1++;
        *H++ = d1;
        continue;

        derefa_body(d1, pt0, creep_unk, creep_nonvar);
        if (pt0 <= H) {
          /* variable is safe */
          *H++ = (CELL)pt0;
          pt1++;
        } else {
          /* bind it, in case it is a local variable */
          d1 = Unsigned(H);
          RESET_VARIABLE(H);
          pt1++;
          H += 1;
          Bind_Local(pt0, d1);
        }
        ENDP(pt0);
        ENDD(d1);
      }
      ENDP(pt1);
      }
      ENDD(d0);
      H[0] = Yap_Module_Name((PredEntry *)SREG);
      ARG1 = (Term) AbsPair(H);

      H += 2;
      LOCK(SignalLock);
      CreepFlag = CalculateStackGap();
#ifdef COROUTINING
      if (ActiveSignals & YAP_WAKEUP_SIGNAL) {
      ActiveSignals &= ~YAP_WAKEUP_SIGNAL;
      UNLOCK(SignalLock);
      ARG2 = Yap_ListOfWokenGoals();
      SREG = (CELL *) (WakeUpCode);
      /* no more goals to wake up */
      Yap_UpdateTimedVar(WokenGoals, TermNil);
      } else      
#endif
      SREG = (CELL *) CreepCode;
      UNLOCK(SignalLock);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,(PredEntry *)(SREG),XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      PREG = ((PredEntry *)(SREG))->CodeOfPred;
      /* for profiler */
      save_pc();
      CACHE_A1();
      JMPNext();

      BOp(procceed, p);
      CACHE_Y_AS_ENV(YREG);
      PREG = CPREG;
      /* for profiler */
      save_pc();
      ENV_YREG = ENV;
#ifdef DEPTH_LIMIT
      DEPTH = ENV_YREG[E_DEPTH];
#endif
      WRITEBACK_Y_AS_ENV();
      JMPNext();
      ENDCACHE_Y_AS_ENV();
      ENDBOp();

      Op(allocate, e);
      CACHE_Y_AS_ENV(YREG);
      PREG = NEXTOP(PREG, e);
      ENV_YREG[E_CP] = (CELL) CPREG;
      ENV_YREG[E_E] = (CELL) ENV;
#ifdef DEPTH_LIMIT
      ENV_YREG[E_DEPTH] = DEPTH;
#endif      /* DEPTH_LIMIT */
      ENV = ENV_YREG;
      ENDCACHE_Y_AS_ENV();
      GONext();
      ENDOp();

      Op(deallocate, e);
      CACHE_Y_AS_ENV(YREG);
      PREG = NEXTOP(PREG, e);
      /* other instructions do depend on S being set by deallocate
       :-( */
      SREG = YREG;
      CPREG = (yamop *) ENV_YREG[E_CP];
      ENV = ENV_YREG = (CELL *) ENV_YREG[E_E];
#ifdef DEPTH_LIMIT
      DEPTH = ENV_YREG[E_DEPTH];
#endif      /* DEPTH_LIMIT */
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
      if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif /* SBA */
      else ENV_YREG = (CELL *)((CELL) ENV_YREG + ENV_Size(CPREG));
      }
#else
      if (ENV_YREG > (CELL *) B)
      ENV_YREG = (CELL *) B;
      else
      ENV_YREG = (CELL *) ((CELL) ENV_YREG + ENV_Size(CPREG));
#endif /* FROZEN_STACKS */
      WRITEBACK_Y_AS_ENV();
#ifndef NO_CHECKING
      /* check stacks */
      check_stack(NoStackDeallocate, H);
#endif
      ENDCACHE_Y_AS_ENV();
      GONext();
      ENDOp();

/**********************************************
*        OPTYap instructions                  *
**********************************************/

#ifdef YAPOR
#include "or.insts.i"
#endif /* YAPOR */
#ifdef TABLING
#include "tab.insts.i"
#include "tab.tries.insts.i"
#endif /* TABLING */



#ifdef BEAM
 extern int eam_am(PredEntry *);
     Op(run_eam, os);
/*
        printf("%p - %p - %p \n", &&run_eam, (PredEntry *) PREG->u.os.s, (int *) PREG->u.os.opcw);
*/
       if (inp==-9000) {
        extern CELL *beam_ALTERNATIVES;
          *beam_ALTERNATIVES= (CELL *) PREG->u.os.opcw;
        beam_ALTERNATIVES++;
        if (OLD_B!=B) goto fail;
#if PUSH_REGS
        Yap_regp=old_regs;
#endif
        return(0);
        } 

        saveregs();
        if (!eam_am((PredEntry *) PREG->u.os.s)) FAIL();
      setregs();
        goto procceed;
        PREG = NEXTOP(PREG, os);
        GONext();
      ENDOp();
#endif


/************************************************************************\
*    Get Instructions                                       *
\************************************************************************/

      Op(get_x_var, xx);
      BEGD(d0);
      d0 = XREG(PREG->u.xx.xr);
      XREG(PREG->u.xx.xl) = d0;
      PREG = NEXTOP(PREG, xx);
      ENDD(d0);
      GONext();
      ENDOp();

      Op(get_y_var, yx);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yx.y;
      d0 = XREG(PREG->u.yx.x);
      PREG = NEXTOP(PREG, yx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      /* The code for get_x_val is hard to follow because I use a
       * lot of jumps. The convention is that in the label
       * gval_X_YREG X refers to the state of the first argument, and
       * YREG to the state of the second argument */
      Op(get_x_val, xx);
      BEGD(d0);
      d0 = XREG(PREG->u.xx.xl);
      deref_head(d0, gvalx_unk);

      /* d0 will keep the first argument */
    gvalx_nonvar:
      /* first argument is bound */
      BEGD(d1);
      d1 = XREG(PREG->u.xx.xr);
      deref_head(d1, gvalx_nonvar_unk);

    gvalx_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, xx);
      UnifyBound(d0, d1);

      BEGP(pt0);
      /* deref second argument */
      deref_body(d1, pt0, gvalx_nonvar_unk, gvalx_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, xx);
      BIND(pt0, d0, bind_gvalx_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gvalx_nonvar_var:
#endif
      GONext();

      ENDP(pt0);
      ENDD(d1);

      BEGP(pt0);
      /* first argument may be unbound */
      deref_body(d0, pt0, gvalx_unk, gvalx_nonvar);
      /* first argument is unbound and in pt0 and in d0 */
      BEGD(d1);
      d1 = XREG(PREG->u.xx.xr);
      deref_head(d1, gvalx_var_unk);

    gvalx_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, xx);
      BIND(pt0, d1, bind_gvalx_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gvalx_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, gvalx_var_unk, gvalx_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, xx);
      UnifyCells(pt0, pt1, uc1, uc2);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc1:
#endif
      GONext();
#ifdef COROUTINING
    uc2:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDD(d1);
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      /* The code for get_y_val mostly uses the code for get_x_val
       */

      Op(get_y_val, yx);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yx.y;
      d0 = *pt0;

      /* From now on, it's just a copy of the code for get_x_val */

      deref_head(d0, gvaly_unk);
    gvaly_nonvar:

      /* first argument is bound */
      d1 = XREG(PREG->u.yx.x);
      deref_head(d1, gvaly_nonvar_unk);
    gvaly_nonvar_nonvar:

      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, yx);
      UnifyBound(d0, d1);

      BEGP(pt1);
      /* deref second argument */
      deref_body(d1, pt1, gvaly_nonvar_unk, gvaly_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, yx);
      BIND(pt1, d0, bind_gvaly_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
    bind_gvaly_nonvar_var:
#endif
      GONext();
      ENDP(pt1);


      /* first argument may be unbound */
      derefa_body(d0, pt0, gvaly_unk, gvaly_nonvar);
      /* first argument is unbound */
      d1 = XREG(PREG->u.yx.x);
      deref_head(d1, gvaly_var_unk);

    gvaly_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, yx);
      BIND(pt0, d1, bind_gvaly_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gvaly_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, gvaly_var_unk, gvaly_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, yx);
      UnifyCells(pt0, pt1, uc3, uc4);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc3:
#endif
      GONext();
#ifdef COROUTINING
    uc4:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(get_atom, xc);
      BEGD(d0);
      BEGD(d1);
      /* fetch arguments */
      d0 = XREG(PREG->u.xc.x);
      d1 = PREG->u.xc.c;

      BEGP(pt0);
      deref_head(d0, gatom_unk);
      /* argument is nonvar */
    gatom_nonvar:
      if (d0 == d1) {
      PREG = NEXTOP(PREG, xc);
      GONext();
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_unk, gatom_nonvar);
      /* argument is a variable */
      PREG = NEXTOP(PREG, xc);
      BIND(pt0, d1, bind_gatom);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gatom:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(get_2atoms, cc);
      BEGD(d0);
      BEGD(d1);
      /* fetch arguments */
      d0 = ARG1;

      BEGP(pt0);
      deref_head(d0, gatom_2unk);
      /* argument is nonvar */
    gatom_2nonvar:
      if (d0 == PREG->u.cc.c1) {
      goto gatom_2b;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_2unk, gatom_2nonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cc.c1, gatom_2b);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cc.c1);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_2b:
      /* fetch arguments */
      d0 = ARG2;
      d1 = PREG->u.cc.c2;

      BEGP(pt0);
      deref_head(d0, gatom_2bunk);
      /* argument is nonvar */
    gatom_2bnonvar:
      if (d0 == d1) {
      PREG = NEXTOP(PREG, cc);
      GONext();
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_2bunk, gatom_2bnonvar);
      /* argument is a variable */
      PREG = NEXTOP(PREG, cc);
      BIND(pt0, d1, gatom_2c);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    gatom_2c:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(get_3atoms, ccc);
      BEGD(d0);
      BEGD(d1);
      /* fetch arguments */
      d0 = ARG1;

      BEGP(pt0);
      deref_head(d0, gatom_3unk);
      /* argument is nonvar */
    gatom_3nonvar:
      if (d0 == PREG->u.ccc.c1) {
      goto gatom_3b;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_3unk, gatom_3nonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.ccc.c1, gatom_3b);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.ccc.c1);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_3b:
      /* fetch arguments */
      d0 = ARG2;

      BEGP(pt0);
      deref_head(d0, gatom_3bunk);
      /* argument is nonvar */
    gatom_3bnonvar:
      if (d0 == PREG->u.ccc.c2) {
      goto gatom_3c;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_3bunk, gatom_3bnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.ccc.c2, gatom_3c);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.ccc.c2);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_3c:
      /* fetch arguments */
      d0 = ARG3;
      d1 = PREG->u.ccc.c3;

      BEGP(pt0);
      deref_head(d0, gatom_3cunk);
      /* argument is nonvar */
    gatom_3cnonvar:
      if (d0 == d1) {
      PREG = NEXTOP(PREG, ccc);
      GONext();
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_3cunk, gatom_3cnonvar);
      /* argument is a variable */
      PREG = NEXTOP(PREG, ccc);
      BIND(pt0, d1, gatom_3d);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    gatom_3d:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(get_4atoms, cccc);
      BEGD(d0);
      BEGD(d1);
      /* fetch arguments */
      d0 = ARG1;

      BEGP(pt0);
      deref_head(d0, gatom_4unk);
      /* argument is nonvar */
    gatom_4nonvar:
      if (d0 == PREG->u.cccc.c1) {
      goto gatom_4b;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_4unk, gatom_4nonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccc.c1, gatom_4b);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccc.c1);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_4b:
      /* fetch arguments */
      d0 = ARG2;

      BEGP(pt0);
      deref_head(d0, gatom_4bunk);
      /* argument is nonvar */
    gatom_4bnonvar:
      if (d0 == PREG->u.cccc.c2) {
      goto gatom_4c;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_4bunk, gatom_4bnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccc.c2, gatom_4c);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccc.c2);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_4c:
      /* fetch arguments */
      d0 = ARG3;

      BEGP(pt0);
      deref_head(d0, gatom_4cunk);
      /* argument is nonvar */
    gatom_4cnonvar:
      if (d0 == PREG->u.cccc.c3) {
      goto gatom_4d;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_4cunk, gatom_4cnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccc.c3, gatom_4d);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccc.c3);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
   gatom_4d:
      /* fetch arguments */
      d0 = ARG4;
      d1 = PREG->u.cccc.c4;

      BEGP(pt0);
      deref_head(d0, gatom_4dunk);
      /* argument is nonvar */
    gatom_4dnonvar:
      if (d0 == d1) {
      PREG = NEXTOP(PREG, cccc);
      GONext();
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_4dunk, gatom_4dnonvar);
      /* argument is a variable */
      PREG = NEXTOP(PREG, cccc);
      BIND(pt0, d1, gatom_4e);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    gatom_4e:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(get_5atoms, ccccc);
      BEGD(d0);
      BEGD(d1);
      /* fetch arguments */
      d0 = ARG1;

      BEGP(pt0);
      deref_head(d0, gatom_5unk);
      /* argument is nonvar */
    gatom_5nonvar:
      if (d0 == PREG->u.ccccc.c1) {
      goto gatom_5b;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_5unk, gatom_5nonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.ccccc.c1, gatom_5b);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.ccccc.c1);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_5b:
      /* fetch arguments */
      d0 = ARG2;

      BEGP(pt0);
      deref_head(d0, gatom_5bunk);
      /* argument is nonvar */
    gatom_5bnonvar:
      if (d0 == PREG->u.ccccc.c2) {
      goto gatom_5c;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_5bunk, gatom_5bnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.ccccc.c2, gatom_5c);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.ccccc.c2);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_5c:
      /* fetch arguments */
      d0 = ARG3;

      BEGP(pt0);
      deref_head(d0, gatom_5cunk);
      /* argument is nonvar */
    gatom_5cnonvar:
      if (d0 == PREG->u.ccccc.c3) {
      goto gatom_5d;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_5cunk, gatom_5cnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.ccccc.c3, gatom_5d);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.ccccc.c3);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
   gatom_5d:
      /* fetch arguments */
      d0 = ARG4;

      BEGP(pt0);
      deref_head(d0, gatom_5dunk);
      /* argument is nonvar */
    gatom_5dnonvar:
      if (d0 == PREG->u.ccccc.c4) {
      goto gatom_5e;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_5dunk, gatom_5dnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.ccccc.c4, gatom_5e);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.ccccc.c4);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
   gatom_5e:
      /* fetch arguments */
      d0 = ARG5;
      d1 = PREG->u.ccccc.c5;

      BEGP(pt0);
      deref_head(d0, gatom_5eunk);
      /* argument is nonvar */
    gatom_5enonvar:
      if (d0 == d1) {
      PREG = NEXTOP(PREG, ccccc);
      GONext();
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_5eunk, gatom_5enonvar);
      /* argument is a variable */
      PREG = NEXTOP(PREG, ccccc);
      BIND(pt0, d1, gatom_5f);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    gatom_5f:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(get_6atoms, cccccc);
      BEGD(d0);
      BEGD(d1);
      /* fetch arguments */
      d0 = ARG1;

      BEGP(pt0);
      deref_head(d0, gatom_6unk);
      /* argument is nonvar */
    gatom_6nonvar:
      if (d0 == PREG->u.cccccc.c1) {
      goto gatom_6b;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_6unk, gatom_6nonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccccc.c1, gatom_6b);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccccc.c1);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_6b:
      /* fetch arguments */
      d0 = ARG2;

      BEGP(pt0);
      deref_head(d0, gatom_6bunk);
      /* argument is nonvar */
    gatom_6bnonvar:
      if (d0 == PREG->u.cccccc.c2) {
      goto gatom_6c;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_6bunk, gatom_6bnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccccc.c2, gatom_6c);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccccc.c2);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_6c:
      /* fetch arguments */
      d0 = ARG3;

      BEGP(pt0);
      deref_head(d0, gatom_6cunk);
      /* argument is nonvar */
    gatom_6cnonvar:
      if (d0 == PREG->u.cccccc.c3) {
      goto gatom_6d;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_6cunk, gatom_6cnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccccc.c3, gatom_6d);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccccc.c3);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
   gatom_6d:
      /* fetch arguments */
      d0 = ARG4;

      BEGP(pt0);
      deref_head(d0, gatom_6dunk);
      /* argument is nonvar */
    gatom_6dnonvar:
      if (d0 == PREG->u.cccccc.c4) {
      goto gatom_6e;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_6dunk, gatom_6dnonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccccc.c4, gatom_6e);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccccc.c4);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
   gatom_6e:
      /* fetch arguments */
      d0 = ARG5;

      BEGP(pt0);
      deref_head(d0, gatom_6eunk);
      /* argument is nonvar */
    gatom_6enonvar:
      if (d0 == PREG->u.cccccc.c5) {
      goto gatom_6f;
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_6eunk, gatom_6enonvar);
      /* argument is a variable */
      BIND(pt0, PREG->u.cccccc.c5, gatom_6f);
#ifdef COROUTINING
      DO_TRAIL(pt0, PREG->u.cccccc.c5);
      if (pt0 < H0) Yap_WakeUp(pt0);
#endif
      ENDP(pt0);
    gatom_6f:
      /* fetch arguments */
      d0 = ARG6;
      d1 = PREG->u.cccccc.c6;

      BEGP(pt0);
      deref_head(d0, gatom_6funk);
      /* argument is nonvar */
    gatom_6fnonvar:
      if (d0 == d1) {
      PREG = NEXTOP(PREG, cccccc);
      GONext();
      }
      else {
      FAIL();
      }

      deref_body(d0, pt0, gatom_6funk, gatom_6fnonvar);
      /* argument is a variable */
      PREG = NEXTOP(PREG, cccccc);
      BIND(pt0, d1, gatom_6g);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    gatom_6g:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      /* The next instructions can lead to either the READ stream
       * or the write stream */

      OpRW(get_list, x);
      BEGD(d0);
      d0 = XREG(PREG->u.x.x);
      deref_head(d0, glist_unk);

    glist_nonvar:
      /* did we find a list? */
      if (!IsPairTerm(d0)) {
      FAIL();
      }
      START_PREFETCH(x);
      PREG = NEXTOP(PREG, x);
      /* enter read mode */
      SREG = RepPair(d0);
      GONext();
      END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, glist_unk, glist_nonvar);
      /* glist var */
      /* enter write mode */
      CACHE_S();
      S_SREG = H;
      START_PREFETCH_W(x);
      PREG = NEXTOP(PREG, x);
      BEGD(d0);
      d0 = AbsPair(S_SREG);
      BIND(pt0, d0, bind_glist);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) {
      Yap_WakeUp(pt0);
      S_SREG = H;
      }
    bind_glist:
#endif
      /* don't put an ENDD just after a label */
      H = S_SREG + 2;
      ENDD(d0);
      WRITEBACK_S(S_SREG);
      GONextW();


      END_PREFETCH_W();
      ENDCACHE_S();
      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

      OpRW(get_struct, xf);
      BEGD(d0);
      d0 = XREG(PREG->u.xf.x);
      deref_head(d0, gstruct_unk);

    gstruct_nonvar:
      if (!IsApplTerm(d0))
      FAIL();
      /* we have met a compound term */
      START_PREFETCH(xf);
      CACHE_S();
      S_SREG = RepAppl(d0);
      /* check functor */
      d0 = (CELL) (PREG->u.xf.f);
      if (*S_SREG != d0) {
      FAIL();
      }
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      PREG = NEXTOP(PREG, xf);
      /* enter read mode */
      GONext();
      END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, gstruct_unk, gstruct_nonvar);
      /* Enter Write mode */
      /* set d1 to be the new structure we are going to create */
      START_PREFETCH_W(xf);
      BEGD(d1);
      d1 = AbsAppl(H);
      BIND(pt0, d1, bind_gstruct);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gstruct:
#endif
      /* now, set pt0 to point to the heap where we are going to
       * build our term */
      pt0 = H;
      ENDD(d1);
      /* first, put the functor */
      d0 = (CELL) (PREG->u.xf.f);
      *pt0++ = d0;
      H = pt0 + PREG->u.xf.a;
      PREG = NEXTOP(PREG, xf);
      /* set SREG */
      SREG = pt0;
      /* update H */
      GONextW();
      END_PREFETCH_W();
      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

      Op(get_float, xc);
      BEGD(d0);
      d0 = XREG(PREG->u.xc.x);
      deref_head(d0, gfloat_unk);

    gfloat_nonvar:
      if (!IsApplTerm(d0))
      FAIL();
      /* we have met a preexisting float */
      START_PREFETCH(xc);
      BEGP(pt0);
      pt0 = RepAppl(d0);
      /* check functor */
      if (*pt0 != (CELL)FunctorDouble) {
      FAIL();
      }
      BEGP(pt1);
      pt1 = RepAppl(PREG->u.xc.c);
      if (
        pt1[1] != pt0[1]
#if SIZEOF_DOUBLE == 2*SIZEOF_INT_P
        || pt1[2] != pt0[2]
#endif
        ) FAIL();
      ENDP(pt1);
      ENDP(pt0);
      PREG = NEXTOP(PREG, xc);
      /* enter read mode */
      GONext();
      END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, gfloat_unk, gfloat_nonvar);
      /* Enter Write mode */
      /* set d1 to be the new structure we are going to create */
      START_PREFETCH(xc);
      BEGD(d1);
      d1 = PREG->u.xc.c;
      PREG = NEXTOP(PREG, xc);
      BIND(pt0, d1, bind_gfloat);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gfloat:
#endif
      GONext();
      ENDD(d1);
      END_PREFETCH();
      ENDP(pt0);

      ENDD(d0);
      ENDOp();

      Op(get_longint, xc);
      BEGD(d0);
      d0 = XREG(PREG->u.xc.x);
      deref_head(d0, glongint_unk);

    glongint_nonvar:
      if (!IsApplTerm(d0))
      FAIL();
      /* we have met a preexisting longint */
      START_PREFETCH(xc);
      BEGP(pt0);
      pt0 = RepAppl(d0);
      /* check functor */
      if (*pt0 != (CELL)FunctorLongInt) {
      FAIL();
      }
      BEGP(pt1);
      pt1 = RepAppl(PREG->u.xc.c);
      if (pt1[1] != pt0[1]) FAIL();
      ENDP(pt1);
      ENDP(pt0);
      PREG = NEXTOP(PREG, xc);
      /* enter read mode */
      GONext();
      END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, glongint_unk, glongint_nonvar);
      /* Enter Write mode */
      /* set d1 to be the new structure we are going to create */
      START_PREFETCH(xc);
      BEGD(d1);
      d1 = PREG->u.xc.c;
      PREG = NEXTOP(PREG, xc);
      BIND(pt0, d1, bind_glongint);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glongint:
#endif
      GONext();
      ENDD(d1);
      END_PREFETCH();
      ENDP(pt0);

      ENDD(d0);
      ENDOp();

      Op(get_bigint, xc);
#ifdef USE_GMP
      BEGD(d0);
      d0 = XREG(PREG->u.xc.x);
      deref_head(d0, gbigint_unk);

    gbigint_nonvar:
      if (!IsApplTerm(d0))
      FAIL();
      /* we have met a preexisting bigint */
      START_PREFETCH(xc);
      BEGP(pt0);
      pt0 = RepAppl(d0);
      /* check functor */
      if (*pt0 != (CELL)FunctorBigInt)
      {
        FAIL();
      }
      if (mpz_cmp(Yap_BigIntOfTerm(d0),Yap_BigIntOfTerm(PREG->u.xc.c)))
      FAIL();
      PREG = NEXTOP(PREG, xc);      
      ENDP(pt0);
      /* enter read mode */
      GONext();
      END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, gbigint_unk, gbigint_nonvar);
      /* Enter Write mode */
      /* set d1 to be the new structure we are going to create */
      START_PREFETCH(xc);
      BEGD(d1);
      d1 = PREG->u.xc.c;
      PREG = NEXTOP(PREG, xc);
      BIND(pt0, d1, bind_gbigint);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_gbigint:
#endif
      GONext();
      ENDD(d1);
      END_PREFETCH();
      ENDP(pt0);

      ENDD(d0);
#else
      FAIL();
#endif
      ENDOp();

/************************************************************************\
*    Optimised Get List Instructions                              *
\************************************************************************/
      OpRW(glist_valx, xx);
      BEGD(d0);
      d0 = XREG(PREG->u.xx.xl);
      deref_head(d0, glist_valx_write);
    glist_valx_read:
      BEGP(pt0);
      /* did we find a list? */
      if (!IsPairTerm(d0))
      FAIL();
      /* enter read mode */
      START_PREFETCH(xx);
      pt0 = RepPair(d0);
      SREG = pt0 + 1;
      /* start unification with first argument */
      d0 = *pt0;
      deref_head(d0, glist_valx_unk);

      /* first argument is in d0 */
    glist_valx_nonvar:
      /* first argument is bound */
      BEGD(d1);
      d1 = XREG(PREG->u.xx.xr);
      deref_head(d1, glist_valx_nonvar_unk);

    glist_valx_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, xx);
      UnifyBound(d0, d1);

      BEGP(pt1);
      /* deref second argument */
      deref_body(d1, pt1, glist_valx_nonvar_unk, glist_valx_nonvar_nonvar);
      /* head bound, argument unbound */
      PREG = NEXTOP(PREG, xx);
      BIND(pt1, d0, bind_glist_valx_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
    bind_glist_valx_nonvar_var:
#endif
      GONext();
      ENDP(pt1);


      ENDD(d1);

      /* head may be unbound */
      derefa_body(d0, pt0, glist_valx_unk, glist_valx_nonvar);
      /* head is unbound, pt0 has the value */
      d0 = XREG(PREG->u.xx.xr);
      deref_head(d0, glist_valx_var_unk);

    glist_valx_var_nonvar:
      /* head is unbound, second arg bound */
      PREG = NEXTOP(PREG, xx);
      BIND_GLOBAL(pt0, d0, bind_glist_valx_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_valx_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d0, pt1, glist_valx_var_unk, glist_valx_var_nonvar);
      /* head and second argument are unbound */
      PREG = NEXTOP(PREG, xx);
      UnifyGlobalRegCells(pt0, pt1, uc5, uc6);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc5:
#endif
      GONext();
#ifdef COROUTINING
    uc6:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, glist_valx_write, glist_valx_read);
      CACHE_S();
      /* enter write mode */
      S_SREG = H;
      BEGD(d1);
      d1 = XREG(PREG->u.xx.xr);
      d0 = AbsPair(S_SREG);
      S_SREG[0] = d1;
      ENDD(d1);
      ALWAYS_START_PREFETCH_W(xx);
#ifdef COROUTINING
      PREG = NEXTOP(PREG, xx);
      H = S_SREG + 2;
      WRITEBACK_S(S_SREG+1);
#endif
      DBIND(pt0, d0, dbind);
#ifndef COROUTINING
      /* include XREG on it */
      PREG = NEXTOP(PREG, xx);
      H = S_SREG + 2;
      WRITEBACK_S(S_SREG+1);
#endif

#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    dbind:
#endif
      ALWAYS_GONextW();
      ALWAYS_END_PREFETCH_W();
      ENDCACHE_S();
      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

      OpRW(glist_valy, xy);
      BEGD(d0);
      d0 = XREG(PREG->u.xy.x);
      deref_head(d0, glist_valy_write);
    glist_valy_read:
      BEGP(pt0);
      /* did we find a list? */
      if (!IsPairTerm(d0))
      FAIL();
      START_PREFETCH(xy);
      /* enter read mode */
      pt0 = RepPair(d0);
      SREG = pt0 + 1;
      /* start unification with first argument */
      d0 = *pt0;
      deref_head(d0, glist_valy_unk);

    glist_valy_nonvar:
      /* first argument is bound */
      BEGD(d1);
      BEGP(pt1);
      pt1 = YREG + PREG->u.xy.y;
      d1 = *pt1;
      PREG = NEXTOP(PREG, xy);
      deref_head(d1, glist_valy_nonvar_unk);

    glist_valy_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      SREG = pt0 + 1;
      UnifyBound(d0, d1);

      /* deref second argument */
      derefa_body(d1, pt1, glist_valy_nonvar_unk, glist_valy_nonvar_nonvar);
      /* first argument bound, second unbound */
      BIND(pt1, d0, bind_glist_valy_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
    bind_glist_valy_nonvar_var:
#endif
      GONext();


      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, glist_valy_unk, glist_valy_nonvar);
      /* first argument is unbound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.xy.y;
      d1 = *pt1;
      deref_head(d1, glist_valy_var_unk);
    glist_valy_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, xy);
      BIND_GLOBAL(pt0, d1, bind_glist_valy_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_valy_var_nonvar:
#endif
      GONext();

      derefa_body(d1, pt1, glist_valy_var_unk, glist_valy_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, xy);
      UnifyGlobalRegCells(pt0, pt1, uc7, uc8);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc7:
#endif
      GONext();
#ifdef COROUTINING
    uc8:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDD(d1);

      END_PREFETCH();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d0, pt0, glist_valy_write, glist_valy_read);
      /* enter write mode */
      START_PREFETCH_W(xy);
      BEGP(pt1);
      pt1 = H;
      d0 = AbsPair(pt1);
      BIND(pt0, d0, bind_glist_valy_write);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_valy_write:
#endif
      BEGD(d0);
      /* include XREG on it */
      d0 = YREG[PREG->u.xy.y];
      pt1[0] = d0;
      ENDD(d0);
      H = pt1 + 2;
      SREG = pt1 + 1;
      ENDP(pt1);
      PREG = NEXTOP(PREG, xy);
      GONextW();
      END_PREFETCH_W();
      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

      Op(gl_void_varx, xx);
      BEGD(d0);
      d0 = XREG(PREG->u.xx.xl);
      deref_head(d0, glist_void_varx_write);
    glist_void_varx_read:
      /* did we find a list? */
      if (!IsPairTerm(d0))
      FAIL();
      ALWAYS_START_PREFETCH(xx);
      /* enter read mode */
      BEGP(pt0);
      pt0 = RepPair(d0);
      d0 = pt0[1];
      XREG(PREG->u.xx.xr) = d0;
      PREG = NEXTOP(PREG, xx);
      ALWAYS_GONext();
      ENDP(pt0);
      ALWAYS_END_PREFETCH();

      BEGP(pt0);
      deref_body(d0, pt0, glist_void_varx_write, glist_void_varx_read);
      /* enter write mode */
      BEGP(pt1);
      pt1 = H;
      /* include XREG on it */
      XREG(PREG->u.xx.xr) =
      Unsigned(pt1 + 1);
      RESET_VARIABLE(pt1);
      RESET_VARIABLE(pt1+1);
      H = pt1 + 2;
      BEGD(d0);
      d0 = AbsPair(pt1);
      BIND(pt0, d0, bind_glist_varx_write);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_varx_write:
#endif
      PREG = NEXTOP(PREG, xx);
      ENDD(d0);
      ENDP(pt1);
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(gl_void_vary, xy);
      BEGD(d0);
      d0 = XREG(PREG->u.xy.x);
      deref_head(d0, glist_void_vary_write);
    glist_void_vary_read:
      /* did we find a list? */
      if (!IsPairTerm(d0))
      FAIL();
      /* enter read mode */
      BEGP(pt0);
      pt0 = RepPair(d0);
      d0 = pt0[1];
      ENDP(pt0);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.xy.y,d0);
#else
      YREG[PREG->u.xy.y] = d0;
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, xy);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, glist_void_vary_write, glist_void_vary_read);
      /* enter write mode */
      BEGP(pt1);
      pt1 = H;
      /* include XREG on it */
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.xy.y,Unsigned(pt1 + 1));
#else
      YREG[PREG->u.xy.y] = Unsigned(pt1 + 1);
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, xy);
      RESET_VARIABLE(pt1);
      RESET_VARIABLE(pt1+1);
      d0 = AbsPair(pt1);
      H = pt1 + 2;
      BIND(pt0, d0, bind_glist_void_vary_write);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_void_vary_write:
#endif
      GONext();
      ENDP(pt1);
      ENDP(pt0);

      ENDD(d0);
      ENDOp();

      Op(gl_void_valx, xx);
      BEGD(d0);
      d0 = XREG(PREG->u.xx.xl);
      deref_head(d0, glist_void_valx_write);
    glist_void_valx_read:
      BEGP(pt0);
      /* did we find a list? */
      if (!IsPairTerm(d0))
      FAIL();
      /* enter read mode */
      pt0 = RepPair(d0)+1;
      /* start unification with first argument */
      d0 = *pt0;
      deref_head(d0, glist_void_valx_unk);

    glist_void_valx_nonvar:
      /* first argument is bound */
      BEGD(d1);
      d1 = XREG(PREG->u.xx.xr);
      deref_head(d1, glist_void_valx_nonvar_unk);

    glist_void_valx_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, xx);
      UnifyBound(d0, d1);

      /* deref second argument */
      BEGP(pt1);
      deref_body(d1, pt1, glist_void_valx_nonvar_unk, glist_void_valx_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, xx);
      BIND(pt1, d0, bind_glist_void_valx_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_glist_void_valx_nonvar_var:
#endif
      GONext();
      ENDP(pt1);
      ENDD(d1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, glist_void_valx_unk, glist_void_valx_nonvar);
      /* first argument is unbound */
      BEGD(d1);
      d1 = XREG(PREG->u.xx.xr);
      deref_head(d1, glist_void_valx_var_unk);

    glist_void_valx_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, xx);
      BIND_GLOBAL(pt0, d1, bind_glist_void_valx_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_glist_void_valx_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, glist_void_valx_var_unk, glist_void_valx_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, xx);
      UnifyGlobalRegCells(pt0, pt1, uc9, uc10);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc9:
#endif
      GONext();
#ifdef COROUTINING
    uc10:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDD(d1);
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d0, pt0, glist_void_valx_write, glist_void_valx_read);
      /* enter write mode */
      BEGP(pt1);
      pt1 = H;
      d0 = AbsPair(SREG);
      BIND(pt0, d0, bind_glist_void_valx_write);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_void_valx_write:
#endif
      BEGD(d0);
      /* include XREG on it */
      d0 = XREG(PREG->u.xx.xr);
      RESET_VARIABLE(pt1);
      pt1[1] = d0;
      H = pt1 + 2;
      ENDD(d0);
      ENDP(pt1);
      PREG = NEXTOP(PREG, xx);
      GONext();
      ENDP(pt0);

      ENDD(d0);
      ENDOp();

      Op(gl_void_valy, xy);
      BEGD(d0);
      d0 = XREG(PREG->u.xy.x);
      deref_head(d0, glist_void_valy_write);
    glist_void_valy_read:
      BEGP(pt0);
      /* did we find a list? */
      if (!IsPairTerm(d0))
      FAIL();
      /* enter read mode */
      pt0 = RepPair(d0)+1;
      /* start unification with first argument */
      d0 = *pt0;
      deref_head(d0, glist_void_valy_unk);

    glist_void_valy_nonvar:
      /* first argument is bound */
      BEGD(d1);
      BEGP(pt1);
      pt1 = YREG+PREG->u.xy.y;
      d1 = *pt1;
      deref_head(d1, glist_void_valy_nonvar_unk);

    glist_void_valy_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, xy);
      UnifyBound(d0, d1);

      /* deref second argument */
      derefa_body(d1, pt1, glist_void_valy_nonvar_unk, glist_void_valy_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, xy);
      BIND(pt1, d0, bind_glist_void_valy_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_glist_void_valy_nonvar_var:
#endif
      GONext();

      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, glist_void_valy_unk, glist_void_valy_nonvar);
      /* first argument is unbound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.xy.y;
      d1 = *pt1;
      deref_head(d1, glist_void_valy_var_unk);

    glist_void_valy_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, xy);
      BIND_GLOBAL(pt0, d1, bind_glist_void_valy_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_glist_void_valy_var_nonvar:
#endif
      GONext();

      deref_body(d1, pt1, glist_void_valy_var_unk, glist_void_valy_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, xy);
      UnifyGlobalRegCells(pt0, pt1, uc11, uc12);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc11:
#endif
      GONext();
#ifdef COROUTINING
    uc12:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDD(d1);
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d0, pt0, glist_void_valy_write, glist_void_valy_read);
      /* enter write mode */
      CACHE_S();
      S_SREG = H;
      d0 = AbsPair(S_SREG);
      BIND(pt0, d0, bind_glist_void_valy_write);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_glist_void_valy_write:
#endif
      /* include XREG on it */
      BEGD(d1);
      d1 = YREG[PREG->u.xy.y];
      RESET_VARIABLE(S_SREG);
      S_SREG[1] = d1;
      ENDD(d1);
      PREG = NEXTOP(PREG, xy);
      H = S_SREG + 2;
      ENDCACHE_S();
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();



/************************************************************************\
*     Unify instructions                                    *
\************************************************************************/

      Op(unify_x_var, ox);
      CACHE_S();
      READ_IN_S();
      BEGD(d0);
      d0 = *S_SREG;
#if SBA
      if (d0 == 0)
      d0 = (CELL)S_SREG;
#endif
      WRITEBACK_S(S_SREG+1);
      ALWAYS_START_PREFETCH(ox);
      XREG(PREG->u.ox.x) = d0;
      PREG = NEXTOP(PREG, ox);
      ALWAYS_GONext();
      ALWAYS_END_PREFETCH();
      ENDD(d0);
      ENDCACHE_S();
      ENDOp();

      OpW(unify_x_var_write, ox);
      CACHE_S();
      READ_IN_S();
      BEGP(pt0);
      pt0 = &XREG(PREG->u.ox.x);
      PREG = NEXTOP(PREG, ox);
      RESET_VARIABLE(S_SREG);
      *pt0 = (CELL) S_SREG;
      WRITEBACK_S(S_SREG+1);
      ENDP(pt0);
      ENDCACHE_S();
      GONextW();
      ENDOpW();

      BOp(unify_l_x_var, ox);
      ALWAYS_START_PREFETCH(ox);
      BEGP(pt0);
      BEGD(d0);
      d0 = SREG[0];
      pt0 = &XREG(PREG->u.ox.x);
      PREG = NEXTOP(PREG, ox);
#if SBA
      if (d0 == 0)
      d0 = (CELL)SREG;
#endif
      *pt0 = d0;
      ALWAYS_GONext();
      ENDD(d0);
      ENDP(pt0);
      ALWAYS_END_PREFETCH();
      ENDBOp();

      BOp(unify_l_x_var_write, ox);
      ALWAYS_START_PREFETCH(ox);
      CACHE_S();
      READ_IN_S();
      BEGP(pt0);
      pt0 = &XREG(PREG->u.ox.x);
      PREG = NEXTOP(PREG, ox);
      RESET_VARIABLE(S_SREG);
      *pt0 = (CELL)S_SREG;
      ENDP(pt0);
      ENDCACHE_S();
      ALWAYS_GONext();
      ENDBOp();
      ALWAYS_END_PREFETCH();

      BOp(unify_x_var2, oxx);
      CACHE_S();
      ALWAYS_START_PREFETCH(oxx);
      READ_IN_S();
      BEGP(pt0);
      pt0 = &XREG(PREG->u.oxx.xr);
      BEGD(d0);
      d0 = S_SREG[0];
      BEGD(d1);
      d1 = S_SREG[1];
#if SBA
      if (d0 == 0)
      d0 = (CELL)S_SREG;
      if (d1 == 0)
      d1 = (CELL)(S_SREG+1);
#endif
      WRITEBACK_S(S_SREG+2);
      XREG(PREG->u.oxx.xl) = d0;
      PREG = NEXTOP(PREG, oxx);
      *pt0 = d1;
      ENDD(d0);
      ENDD(d1);
      ENDP(pt0);
      ALWAYS_GONext();
      ENDBOp();
      ALWAYS_END_PREFETCH();
      ENDCACHE_S();

      OpW(unify_x_var2_write, oxx);
      CACHE_S();
      READ_IN_S();
      BEGP(pt0);
      pt0 = &XREG(PREG->u.oxx.xr);
      RESET_VARIABLE(S_SREG);
      XREG(PREG->u.oxx.xl) = (CELL) S_SREG;
      S_SREG++;
      PREG = NEXTOP(PREG, oxx);
      RESET_VARIABLE(S_SREG);
      *pt0 = (CELL) S_SREG;
      ENDP(pt0);
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      GONextW();
      ENDOpW();

      BOp(unify_l_x_var2, oxx);
      ALWAYS_START_PREFETCH(oxx);
      CACHE_S();
      READ_IN_S();
      BEGP(pt0);
      pt0 = &XREG(PREG->u.oxx.xr);
      BEGD(d0);
      d0 = S_SREG[0];
      BEGD(d1);
      d1 = S_SREG[1];
#if SBA
      if (d0 == 0)
      XREG(PREG->u.oxx.xl) = (CELL)S_SREG;
      else
#endif
      XREG(PREG->u.oxx.xl) = d0;
      PREG = NEXTOP(PREG, oxx);
#if SBA
      if (d1 == 0)
      *pt0 = (CELL)(S_SREG+1);
      else
#endif
      *pt0 = d1;
      ENDD(d0);
      ENDD(d1);
      ENDP(pt0);
      ENDCACHE_S();
      ALWAYS_GONext();
      ENDBOp();
      ALWAYS_END_PREFETCH();

      Op(unify_l_x_var2_write, oxx);
      CACHE_S();
      READ_IN_S();
      BEGP(pt0);
      pt0 = &XREG(PREG->u.oxx.xr);
      XREG(PREG->u.oxx.xl) = (CELL) S_SREG;
      RESET_VARIABLE(S_SREG);
      S_SREG++;
      *pt0 = (CELL) S_SREG;
      PREG = NEXTOP(PREG, oxx);
      RESET_VARIABLE(S_SREG);
      ENDP(pt0);
      ENDCACHE_S();
      GONext();
      ENDOp();

      Op(unify_y_var, oy);
      BEGD(d0);
      d0 = *SREG++;
#if defined(SBA)
#ifdef FROZEN_STACKS
      if (d0 == 0) {
      Bind_Local(YREG+PREG->u.oy.y,(CELL)(SREG-1));
      } else {
      Bind_Local(YREG+PREG->u.oy.y,d0);
      }
#else
      if (d0 == 0) {
      YREG[PREG->u.oy.y] = (CELL)(SREG-1);
      } else
      YREG[PREG->u.oy.y] = d0;
#endif /* FROZEN_STACKS */
#else
      YREG[PREG->u.oy.y] = d0;
#endif /* SBA */
      PREG = NEXTOP(PREG, oy);
      GONext();
      ENDD(d0);
      ENDOp();

      OpW(unify_y_var_write, oy);
      CACHE_S();
      READ_IN_S();
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.oy.y,(CELL) S_SREG);
#else
      YREG[PREG->u.oy.y] = (CELL) S_SREG;
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, oy);
      RESET_VARIABLE(S_SREG);
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      GONextW();
      ENDOpW();

      Op(unify_l_y_var, oy);
      BEGD(d0);
      d0 = SREG[0];
#ifdef SBA
#ifdef FROZEN_STACKS
      if (d0 == 0) {
      Bind_Local(YREG+PREG->u.oy.y,(CELL)SREG);
      } else {
      Bind_Local(YREG+PREG->u.oy.y,d0);
      }
#else
      if (d0 == 0) {
      YREG[PREG->u.oy.y] = (CELL)SREG;
      } else {
      YREG[PREG->u.oy.y] = d0;
      }
#endif /* FROZEN_STACKS */
#else
      YREG[PREG->u.oy.y] = d0;
#endif /* SBA */
      PREG = NEXTOP(PREG, oy);
      GONext();
      ENDD(d0);
      ENDOp();

      Op(unify_l_y_var_write, oy);
      CACHE_S();
      READ_IN_S();
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.oy.y,(CELL) S_SREG);
#else
      YREG[PREG->u.oy.y] = (CELL) S_SREG;
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, oy);
      RESET_VARIABLE(S_SREG);
      ENDCACHE_S();
      GONext();
      ENDOp();

      OpW(unify_x_val_write, ox);
      /* we are in write mode */
      *SREG++ = XREG(PREG->u.ox.x);
      PREG = NEXTOP(PREG, ox);
      GONextW();
      ENDOpW();

      /* We assume the value in X is pointing to an object in the
       * global stack */
      Op(unify_x_val, ox);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, uvalx_unk);

    uvalx_nonvar:
      /* first argument is bound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, uvalx_nonvar_unk);

    uvalx_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      UnifyBound(d0, d1);

      /* deref second argument */
      /* pt0 is in the structure and pt1 the register */
      BEGP(pt1);
      deref_body(d1, pt1, uvalx_nonvar_unk, uvalx_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      BIND(pt1, d0, bind_uvalx_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_uvalx_nonvar_var:
#endif
      GONext();
     ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, uvalx_unk, uvalx_nonvar);
      /* first argument is unbound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, uvalx_var_unk);

    uvalx_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      BIND_GLOBAL(pt0, d1, bind_uvalx_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_uvalx_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, uvalx_var_unk, uvalx_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      UnifyGlobalRegCells(pt0, pt1, uc13, uc14);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc13:
#endif
      GONext();
#ifdef COROUTINING
    uc14:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(unify_l_x_val_write, ox);
      /* we are in write mode */
      SREG[0] = XREG(PREG->u.ox.x);
      PREG = NEXTOP(PREG, ox);
      GONext();
      ENDOp();

      /* We assume the value in X is pointing to an object in the
       * global stack */
      Op(unify_l_x_val, ox);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ulvalx_unk);

    ulvalx_nonvar:
      /* first argument is bound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, ulvalx_nonvar_unk);

    ulvalx_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, ox);
      UnifyBound(d0, d1);

      BEGP(pt1);
      /* deref second argument */
      deref_body(d1, pt1, ulvalx_nonvar_unk, ulvalx_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, ox);
      BIND(pt1, d0, bind_ulvalx_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_ulvalx_nonvar_var:
#endif
      GONext();
      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, ulvalx_unk, ulvalx_nonvar);
      /* first argument is unbound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, ulvalx_var_unk);

    ulvalx_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, ox);
      BIND_GLOBAL(pt0, d1, bind_ulvalx_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulvalx_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, ulvalx_var_unk, ulvalx_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, ox);
      UnifyGlobalRegCells(pt0, pt1, uc15, uc16);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc15:
#endif
      GONext();
#ifdef COROUTINING
    uc16:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      OpW(unify_y_val_write, oy);
      /* we are in write mode */
      BEGD(d0);
      d0 = YREG[PREG->u.oy.y];
#if SBA
      if (d0 == 0) /* free variable */
      *SREG++ = (CELL)(YREG+PREG->u.oy.y);
      else
#endif
      *SREG++ = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, oy);
      GONextW();
      ENDOpW();

      /* We assume the value in X is pointing to an object in the
       * global stack */
      Op(unify_y_val, oy);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, uvaly_unk);

    uvaly_nonvar:
      /* first argument is bound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y; 
      d1 = *pt1;
      deref_head(d1, uvaly_nonvar_unk);

    uvaly_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      UnifyBound(d0, d1);

      /* deref second argument */
      derefa_body(d1, pt1, uvaly_nonvar_unk, uvaly_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      BIND(pt1, d0, bind_uvaly_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_uvaly_nonvar_var:
#endif
      GONext();
      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, uvaly_unk, uvaly_nonvar);
      /* first argument is unbound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y;
      d1 = *pt1;
      deref_head(d1, uvaly_var_unk);

    uvaly_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      BIND_GLOBAL(pt0, d1, bind_uvaly_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_uvaly_var_nonvar:
#endif
      GONext();

      derefa_body(d1, pt1, uvaly_var_unk, uvaly_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      UnifyGlobalRegCells(pt0, pt1, uc17, uc18);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc17:
#endif
      GONext();
#ifdef COROUTINING
    uc18:
      DO_TRAIL(pt1, (CELL)pt1);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(unify_l_y_val_write, oy);
      /* we are in write mode */
      BEGD(d0);
      d0 = YREG[PREG->u.oy.y];
#if SBA
      if (d0 == 0) /* new variable */
      SREG[0] = (CELL)(YREG+PREG->u.oy.y);
      else
#endif
      SREG[0] = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, oy);
      GONext();
      ENDOp();

      /* We assume the value in X is pointing to an object in the
       * global stack */
      Op(unify_l_y_val, oy);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ulvaly_unk);

    ulvaly_nonvar:
      /* first argument is bound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y;
      d1 = *pt1;
      deref_head(d1, ulvaly_nonvar_unk);

    ulvaly_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, oy);
      UnifyBound(d0, d1);

      /* deref second argument */
      derefa_body(d1, pt1, ulvaly_nonvar_unk, ulvaly_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, oy);
      BIND(pt1, d0, bind_ulvaly_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_ulvaly_nonvar_var:
#endif
      GONext();
      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, ulvaly_unk, ulvaly_nonvar);
      /* first argument is unbound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y;
      d1 = *pt1;
      deref_head(d1, ulvaly_var_unk);

    ulvaly_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, oy);
      BIND_GLOBAL(pt0, d1, bind_ulvaly_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulvaly_var_nonvar:
#endif
      GONext();

      /* Here we are in trouble: we have a clash between pt1 and
       * SREG. We address this by storing SREG in d0 for the duration. */
      derefa_body(d1, pt1, ulvaly_var_unk, ulvaly_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, oy);
      UnifyGlobalRegCells(pt0, pt1, uc19, uc20);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc19:
#endif
      GONext();
#ifdef COROUTINING
    uc20:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      OpW(unify_x_loc_write, ox);
      /* we are in write mode */
      BEGD(d0);
      d0 = XREG(PREG->u.ox.x);
      deref_head(d0, unify_x_loc_unk);
    unify_x_loc_nonvar:
      *SREG++ = d0;
      PREG = NEXTOP(PREG, ox);
      GONextW();

      BEGP(pt0);
      deref_body(d0, pt0, unify_x_loc_unk, unify_x_loc_nonvar);
      /* move ahead in the instructions */
      PREG = NEXTOP(PREG, ox);
      /* d0 is a variable, check whether we need to globalise it */
      if (pt0 < H) {
      /* variable is global */
      *SREG++ = Unsigned(pt0);
      GONextW();
      }
      else {
      /* bind our variable to the structure */
      CACHE_S();
      READ_IN_S();
      Bind_Local(pt0, Unsigned(S_SREG));
      RESET_VARIABLE(S_SREG);
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      GONextW();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOpW();

      /* In the next instructions, we do not know anything about
       * what is in X */
      Op(unify_x_loc, ox);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, uvalx_loc_unk);

    uvalx_loc_nonvar:
      /* first argument is bound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, uvalx_loc_nonvar_unk);

    uvalx_loc_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      UnifyBound(d0, d1);

      BEGP(pt1);
      /* deref second argument */
      deref_body(d1, pt1, uvalx_loc_nonvar_unk, uvalx_loc_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      BIND(pt1, d0, bind_uvalx_loc_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_uvalx_loc_nonvar_var:
#endif
      GONext();
      ENDP(pt1);


      /* first argument may be unbound */
      derefa_body(d0, pt0, uvalx_loc_unk, uvalx_loc_nonvar);
      /* first argument is unbound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, uvalx_loc_var_unk);

    uvalx_loc_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      BIND_GLOBAL(pt0, d1, bind_uvalx_loc_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_uvalx_loc_var_nonvar:
#endif
      GONext();

      /* Here we are in trouble: we have a clash between pt1 and
       * SREG. We address this by storing SREG in d0 for the duration. */
      BEGP(pt1);
      deref_body(d1, pt1, uvalx_loc_var_unk, uvalx_loc_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, ox);
      SREG++;
      UnifyGlobalRegCells(pt0, pt1, uc21, uc22);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc21:
#endif
      GONext();
#ifdef COROUTINING
    uc22:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(unify_l_x_loc_write, ox);
      /* we are in write mode */
      BEGD(d0);
      d0 = XREG(PREG->u.ox.x);
      deref_head(d0, ulnify_x_loc_unk);
    ulnify_x_loc_nonvar:
      SREG[0] = d0;
      PREG = NEXTOP(PREG, ox);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, ulnify_x_loc_unk, ulnify_x_loc_nonvar);
      /* d0 is a variable, check whether we need to globalise it */
      PREG = NEXTOP(PREG, ox);
      if (pt0 < H) {
      /* variable is global */
      SREG[0] = Unsigned(pt0);
      GONext();
      }
      else {
      /* create a new Heap variable and bind our variable to it */
      Bind_Local(pt0, Unsigned(SREG));
      RESET_VARIABLE(SREG);
      GONext();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOpW();

      /* In the next instructions, we do not know anything about
       * what is in X */
      Op(unify_l_x_loc, ox);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ulvalx_loc_unk);

    ulvalx_loc_nonvar:
      /* first argument is bound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, ulvalx_loc_nonvar_unk);

    ulvalx_loc_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, ox);
      UnifyBound(d0, d1);

      /* deref second argument */
      deref_body(d1, pt0, ulvalx_loc_nonvar_unk, ulvalx_loc_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, ox);
      BIND(pt0, d0, bind_ulvalx_loc_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulvalx_loc_nonvar_var:
#endif
      GONext();

      /* first argument may be unbound */
      derefa_body(d0, pt0, ulvalx_loc_unk, ulvalx_loc_nonvar);
      /* first argument is unbound */
      d1 = XREG(PREG->u.ox.x);
      deref_head(d1, ulvalx_loc_var_unk);

    ulvalx_loc_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, ox);
      BIND_GLOBAL(pt0, d1, bind_ulvalx_loc_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulvalx_loc_var_nonvar:
#endif
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, ulvalx_loc_var_unk, ulvalx_loc_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, ox);
      UnifyGlobalRegCells(pt0, pt1, uc23, uc24);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc23:
#endif
      GONext();
#ifdef COROUTINING
    uc24:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      OpW(unify_y_loc_write, oy);
      /* we are in write mode */
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG+PREG->u.oy.y;
      d0 = *pt0;
      deref_head(d0, unify_y_loc_unk);
    unify_y_loc_nonvar:
      *SREG++ = d0;
      PREG = NEXTOP(PREG, oy);
      GONextW();

      derefa_body(d0, pt0, unify_y_loc_unk, unify_y_loc_nonvar);
      /* d0 is a variable, check whether we need to globalise it */
      PREG = NEXTOP(PREG, oy);
      if (pt0 < H) {
      /* variable is global */
      *SREG++ = Unsigned(pt0);
      GONextW();
      }
      else {
      /* create a new Heap variable and bind our variable to it */
      CACHE_S();
      READ_IN_S();
      Bind_Local(pt0, Unsigned(S_SREG));
      RESET_VARIABLE(S_SREG);
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      GONextW();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOpW();

      Op(unify_y_loc, oy);
      /* we are in read mode */
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, uvaly_loc_unk);

    uvaly_loc_nonvar:
      /* structure is bound */
      BEGP(pt1);
      pt1 =  YREG+PREG->u.oy.y;
      d1 = *pt1;
      deref_head(d1, uvaly_loc_nonvar_unk);

    uvaly_loc_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      UnifyBound(d0, d1);

      /* deref second argument */
      derefa_body(d1, pt1, uvaly_loc_nonvar_unk, uvaly_loc_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      BIND(pt1, d0, bind_uvaly_loc_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_uvaly_loc_nonvar_var:
#endif
      GONext();
      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, uvaly_loc_unk, uvaly_loc_nonvar);
      /* first argument is unbound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y; 
      d1 = *pt1;
      deref_head(d1, uvaly_loc_var_unk);

    uvaly_loc_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      BIND_GLOBAL(pt0, d1, bind_uvaly_loc_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_uvaly_loc_var_nonvar:
#endif
      GONext();

      /* Here we are in trouble: we have a clash between pt1 and
       * SREG. We address this by storing SREG in d0 for the duration. */
      derefa_body(d1, pt1, uvaly_loc_var_unk, uvaly_loc_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, oy);
      SREG++;
      UnifyGlobalRegCells(pt0, pt1, uc25, uc26);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc25:
#endif
      GONext();
#ifdef COROUTINING
    uc26:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(unify_l_y_loc_write, oy);
      /* we are in write mode */
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG+PREG->u.oy.y;
      d0 = *pt0;
      deref_head(d0, ulunify_y_loc_unk);
    ulunify_y_loc_nonvar:
      SREG[0] = d0;
      PREG = NEXTOP(PREG, oy);
      GONext();

      derefa_body(d0, pt0, ulunify_y_loc_unk, ulunify_y_loc_nonvar);
      /* d0 is a variable, check whether we need to globalise it */
      PREG = NEXTOP(PREG, oy);
      if (pt0 < H) {
      /* variable is global */
      SREG[0] = Unsigned(pt0);
      GONext();
      }
      else {
      /* create a new Heap variable and bind our variable to it */
      CACHE_S();
      READ_IN_S();
      Bind_Local(pt0, Unsigned(S_SREG));
      RESET_VARIABLE(S_SREG);
      ENDCACHE_S();
      GONext();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(unify_l_y_loc, oy);
      /* else we are in read mode */
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ulvaly_loc_unk);

    ulvaly_loc_nonvar:
      /* structure is bound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y;
      d1 = *pt1;
      deref_head(d1, ulvaly_loc_nonvar_unk);

    ulvaly_loc_nonvar_nonvar:
      /* both arguments are bound */
      /* we may have to bind structures */
      PREG = NEXTOP(PREG, oy);
      UnifyBound(d0, d1);

      /* deref second argument */
      derefa_body(d1, pt1, ulvaly_loc_nonvar_unk, ulvaly_loc_nonvar_nonvar);
      /* first argument bound, second unbound */
      PREG = NEXTOP(PREG, oy);
      BIND(pt1, d0, bind_ulvaly_loc_nonvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt1, d0);
      if (pt1 < H0) Yap_WakeUp(pt1);
  bind_ulvaly_loc_nonvar_var:
#endif
      GONext();
      ENDP(pt1);

      /* first argument may be unbound */
      derefa_body(d0, pt0, ulvaly_loc_unk, ulvaly_loc_nonvar);
      /* first argument is unbound */
      BEGP(pt1);
      pt1 = YREG+PREG->u.oy.y;
      d1 = *pt1;
      deref_head(d1, ulvaly_loc_var_unk);

    ulvaly_loc_var_nonvar:
      /* first unbound, second bound */
      PREG = NEXTOP(PREG, oy);
      BIND_GLOBAL(pt0, d1, bind_ulvaly_loc_var_nonvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulvaly_loc_var_nonvar:
#endif
      GONext();

      /* Here we are in trouble: we have a clash between pt1 and
       * SREG. We address this by storing SREG in d0 for the duration. */
      derefa_body(d1, pt1, ulvaly_loc_var_unk, ulvaly_loc_var_nonvar);
      /* both arguments are unbound */
      PREG = NEXTOP(PREG, oy);
      UnifyGlobalRegCells(pt0, pt1, uc27, uc28);
#ifdef COROUTINING
      DO_TRAIL(pt0, (CELL)pt1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    uc27:
#endif
      GONext();
#ifdef COROUTINING
    uc28:
      DO_TRAIL(pt1, (CELL)pt0);
      if (pt1 < H0) Yap_WakeUp(pt1);
      GONext();
#endif
      ENDP(pt1);
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      OpW(unify_void_write, o);
      CACHE_S();
      READ_IN_S();
      PREG = NEXTOP(PREG, o);
      RESET_VARIABLE(S_SREG);
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      GONextW();
      ENDOpW();

      Op(unify_void, o);
      SREG++;
      PREG = NEXTOP(PREG, o);
      GONext();
      ENDOp();

      Op(unify_l_void_write, o);
      PREG = NEXTOP(PREG, o);
      RESET_VARIABLE(SREG);
      GONext();
      ENDOp();

      Op(unify_l_void, o);
      PREG = NEXTOP(PREG, o);
      GONext();
      ENDOp();

      OpW(unify_n_voids_write, os);
      BEGD(d0);
      CACHE_S();
      d0 = PREG->u.os.s;
      READ_IN_S();
      PREG = NEXTOP(PREG, os);
      for (; d0 > 0; d0--) {
      RESET_VARIABLE(S_SREG);
      S_SREG++;
      }
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      ENDD(d0);
      GONextW();
      ENDOpW();

      Op(unify_n_voids, os);
      SREG += PREG->u.os.s;
      PREG = NEXTOP(PREG, os);
      GONext();
      ENDOp();

      Op(unify_l_n_voids_write, os);
      BEGD(d0);
      d0 = PREG->u.os.s;
      PREG = NEXTOP(PREG, os);
      CACHE_S();
      READ_IN_S();
      for (; d0 > 0; d0--) {
      RESET_VARIABLE(S_SREG);
      S_SREG++;
      }
      ENDCACHE_S();
      ENDD(d0);
      GONext();
      ENDOp();

      Op(unify_l_n_voids, os);
      PREG = NEXTOP(PREG, os);
      GONext();
      ENDOp();

      OpW(unify_atom_write, oc);
      * SREG++ = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      GONextW();
      ENDOpW();

      Op(unify_atom, oc);
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG++;
      d0 = *pt0;
      deref_head(d0, uatom_unk);
    uatom_nonvar:
      if (d0 != PREG->u.oc.c) {
      FAIL();
      }
      PREG = NEXTOP(PREG, oc);
      GONext();

      derefa_body(d0, pt0, uatom_unk, uatom_nonvar);
      d0 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(pt0, d0, bind_uatom);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_uatom:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(unify_l_atom_write, oc);
      SREG[0] = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      GONext();
      ENDOp();

      Op(unify_l_atom, oc);
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *SREG;
      deref_head(d0, ulatom_unk);
    ulatom_nonvar:
      if (d0 != PREG->u.oc.c) {
      FAIL();
      }
      PREG = NEXTOP(PREG, oc);
      GONext();

      derefa_body(d0, pt0, ulatom_unk, ulatom_nonvar);
      d0 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(pt0, d0, bind_ulatom);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulatom:
#endif
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      OpW(unify_n_atoms_write, osc);
      BEGD(d0);
      BEGD(d1);
      d0 = PREG->u.osc.s;
      d1 = PREG->u.osc.c;
      /* write N atoms */
      CACHE_S();
      READ_IN_S();
      PREG = NEXTOP(PREG, osc);
      for (; d0 > 0; d0--)
      *S_SREG++ = d1;
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      ENDD(d1);
      ENDD(d0);
      GONextW();
      ENDOpW();

      Op(unify_n_atoms, osc);
      {
      register Int i = PREG->u.osc.s;           /* not enough registers */

      BEGD(d1);
      d1 = PREG->u.osc.c;
      for (; i > 0; i--) {
        BEGD(d0);
        BEGP(pt0);
        pt0 = SREG++;
        d0 = *pt0;
        deref_head(d0, uatom_n_var);
      uatom_n_nonvar:
        if (d0 != d1) {
          FAIL();
        }
        continue;

        derefa_body(d0, pt0, uatom_n_var, uatom_n_nonvar);
        BIND_GLOBAL(pt0, d1, bind_unlatom);
#ifdef COROUTINING
        DO_TRAIL(pt0, d1);
        if (pt0 < H0) Yap_WakeUp(pt0);
      bind_unlatom:
        continue;
#endif
        ENDP(pt0);
        ENDD(d0);
      }
      ENDD(d1);
      }
      PREG = NEXTOP(PREG, osc);
      GONext();
      ENDOp();

      Op(unify_float, oc);
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG++;
      d0 = *pt0;
      deref_head(d0, ufloat_unk);
    ufloat_nonvar:
      if (!IsApplTerm(d0)) {
      FAIL();     
      }
      /* look inside term */
      BEGP(pt0);
      pt0 = RepAppl(d0);
      BEGD(d0);
      d0 = *pt0;
      if (d0 != (CELL)FunctorDouble) {
      FAIL();
      }
      ENDD(d0);
      BEGP(pt1);
      pt1 = RepAppl(PREG->u.oc.c);
      PREG = NEXTOP(PREG, oc);
      if (
        pt1[1] != pt0[1]
#if SIZEOF_DOUBLE == 2*SIZEOF_INT_P
        || pt1[2] != pt0[2]
#endif
        ) FAIL();
      ENDP(pt1);
      ENDP(pt0);
      GONext();

      derefa_body(d0, pt0, ufloat_unk, ufloat_nonvar);
      BEGD(d1);
      d1 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(pt0, d1, bind_ufloat);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ufloat:
#endif
      GONext();
      ENDD(d1);
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(unify_l_float, oc);
      BEGD(d0);
      CACHE_S();
      READ_IN_S();
      d0 = *S_SREG;
      deref_head(d0, ulfloat_unk);
    ulfloat_nonvar:
      if (!IsApplTerm(d0)) {
      FAIL();     
      }
      BEGP(pt0);
      pt0 = RepAppl(d0);
      BEGD(d0);
      d0 = *pt0;
      if (d0 != (CELL)FunctorDouble) {
      FAIL();
      }
      ENDD(d0);
      BEGP(pt1);
      pt1 = RepAppl(PREG->u.oc.c);
      PREG = NEXTOP(PREG, oc);
      if (
        pt1[1] != pt0[1]
#if SIZEOF_DOUBLE == 2*SIZEOF_INT_P
        || pt1[2] != pt0[2]
#endif
        ) FAIL();
      ENDP(pt1);
      ENDP(pt0);
      GONext();

      derefa_body(d0, S_SREG, ulfloat_unk, ulfloat_nonvar);
      BEGD(d1);
      d1 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(S_SREG, d1, bind_ulfloat);
#ifdef COROUTINING
      DO_TRAIL(S_SREG, d1);
      if (S_SREG < H0) Yap_WakeUp(S_SREG);
  bind_ulfloat:
#endif
      GONext();
      ENDD(d1);
      ENDCACHE_S();
      ENDD(d0);
      ENDOp();

      Op(unify_longint, oc);
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG++;
      d0 = *pt0;
      deref_head(d0, ulongint_unk);
    ulongint_nonvar:
      /* look inside term */
      if (!IsApplTerm(d0)) {
      FAIL();     
      }
      BEGP(pt0);
      pt0 = RepAppl(d0);
      BEGD(d0);
      d0 = *pt0;
      if (d0 != (CELL)FunctorLongInt) {
      FAIL();
      }
      ENDD(d0);
      BEGP(pt1);
      pt1 = RepAppl(PREG->u.oc.c);
      PREG = NEXTOP(PREG, oc);
      if (pt1[1] != pt0[1]) FAIL();
      ENDP(pt1);
      ENDP(pt0);
      GONext();

      derefa_body(d0, pt0, ulongint_unk, ulongint_nonvar);
      BEGD(d1);
      d1 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(pt0, d1, bind_ulongint);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulongint:
#endif
      GONext();
      ENDD(d1);
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(unify_l_longint, oc);
      BEGD(d0);
      CACHE_S();
      READ_IN_S();
      d0 = *S_SREG;
      deref_head(d0, ullongint_unk);
    ullongint_nonvar:
      if (!IsApplTerm(d0)) {
      FAIL();     
      }
      BEGP(pt0);
      pt0 = RepAppl(d0);
      BEGD(d0);
      d0 = *pt0;
      if (d0 != (CELL)FunctorLongInt) {
      FAIL();
      }
      ENDD(d0);
      BEGP(pt1);
      pt1 = RepAppl(PREG->u.oc.c);
      PREG = NEXTOP(PREG, oc);
      if (pt1[1] != pt0[1]) FAIL();
      ENDP(pt1);
      ENDP(pt0);
      GONext();

      derefa_body(d0, S_SREG, ullongint_unk, ullongint_nonvar);
      BEGD(d1);
      d1 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(S_SREG, d1, bind_ullongint);
#ifdef COROUTINING
      DO_TRAIL(S_SREG, d1);
      if (S_SREG < H0) Yap_WakeUp(S_SREG);
  bind_ullongint:
#endif
      GONext();
      ENDD(d1);
      ENDCACHE_S();
      ENDD(d0);
      ENDOp();

      Op(unify_bigint, oc);
#ifdef USE_GMP
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG++;
      d0 = *pt0;
      deref_head(d0, ubigint_unk);
    ubigint_nonvar:
      /* look inside term */
      if (!IsApplTerm(d0)) {
      FAIL();     
      }
      BEGP(pt0);
      pt0 = RepAppl(d0);
      BEGD(d1);
      d1 = *pt0;
      if (d1 != (CELL)FunctorBigInt)
      {
      FAIL();
      }
      ENDD(d1);
      if (mpz_cmp(Yap_BigIntOfTerm(d0),Yap_BigIntOfTerm(PREG->u.oc.c)))
      FAIL();
      PREG = NEXTOP(PREG, oc);
      ENDP(pt0);
      GONext();

      derefa_body(d0, pt0, ubigint_unk, ubigint_nonvar);
      BEGD(d1);
      d1 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(pt0, d1, bind_ubigint);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ubigint:
#endif
      GONext();
      ENDD(d1);
      ENDP(pt0);
      ENDD(d0);
#else
      FAIL();
#endif
      ENDOp();

      Op(unify_l_bigint, oc);
#ifdef USE_GMP
      BEGD(d0);
      CACHE_S();
      READ_IN_S();
      d0 = *S_SREG;
      deref_head(d0, ulbigint_unk);
    ulbigint_nonvar:
      if (!IsApplTerm(d0)) {
      FAIL();     
      }
      BEGP(pt0);
      pt0 = RepAppl(d0);
      BEGD(d0);
      d0 = *pt0;
      if (d0 != (CELL)FunctorBigInt)
      {
      FAIL();
      }
      ENDD(d0);
      if (mpz_cmp(Yap_BigIntOfTerm(d0),Yap_BigIntOfTerm(PREG->u.oc.c)))
      FAIL();
      PREG = NEXTOP(PREG, oc);
      ENDP(pt0);
      GONext();

      derefa_body(d0, S_SREG, ulbigint_unk, ulbigint_nonvar);
      BEGD(d1);
      d1 = PREG->u.oc.c;
      PREG = NEXTOP(PREG, oc);
      BIND_GLOBAL(S_SREG, d1, bind_ulbigint);
#ifdef COROUTINING
      DO_TRAIL(S_SREG, d1);
      if (S_SREG < H0) Yap_WakeUp(S_SREG);
  bind_ulbigint:
#endif
      GONext();
      ENDD(d1);
      ENDCACHE_S();
      ENDD(d0);
#else
      FAIL();
#endif
      ENDOp();

      OpW(unify_list_write, o);
      PREG = NEXTOP(PREG, o);
      BEGD(d0);
      d0 = AbsPair(H);
      CACHE_S();
      READ_IN_S();
      SP -= 2;
      SP[0] = WRITE_MODE;
      SP[1] = Unsigned(S_SREG + 1);
      S_SREG[0] = d0;
      S_SREG = H;
      H = S_SREG + 2;
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      GONextW();
      ENDD(d0);
      ENDOpW();

      OpRW(unify_list, o);
      *--SP = Unsigned(SREG + 1);
      *--SP = READ_MODE;
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ulist_unk);
    ulist_nonvar:
      if (!IsPairTerm(d0)) {
      FAIL();
      }
      /* we continue in read mode */
      START_PREFETCH(o);
      SREG = RepPair(d0);
      PREG = NEXTOP(PREG, o);
      GONext();
      END_PREFETCH();

      derefa_body(d0, pt0, ulist_unk, ulist_nonvar);
      /* we enter write mode */
      START_PREFETCH_W(o);
      CACHE_S();
      READ_IN_S();
      S_SREG = H;
      PREG = NEXTOP(PREG, o);
      H = S_SREG + 2;
      d0 = AbsPair(S_SREG);
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      BIND_GLOBAL(pt0, d0, bind_ulist_var);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ulist_var:
#endif
      GONextW();
      END_PREFETCH_W();

      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

      OpW(unify_l_list_write, o);
      /* we continue in write mode */
      BEGD(d0);
      d0 = AbsPair(H);
      PREG = NEXTOP(PREG, o);
      CACHE_S();
      READ_IN_S();
      S_SREG[0] = d0;
      S_SREG = H;
      H = S_SREG + 2;
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      GONextW();
      ENDD(d0);
      ENDOpW();

      OpRW(unify_l_list, o);
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ullist_unk);
    ullist_nonvar:
      START_PREFETCH(o);
      if (!IsPairTerm(d0)) {
      FAIL();
      }
      /* we continue in read mode */
      PREG = NEXTOP(PREG, o);
      SREG = RepPair(d0);
      GONext();
      END_PREFETCH();

      derefa_body(d0, pt0, ullist_unk, ullist_nonvar);
      /* we enter write mode */
      START_PREFETCH_W(o);
      PREG = NEXTOP(PREG, o);
      CACHE_S();
      READ_IN_S();
      S_SREG = H;
      H = S_SREG + 2;
      d0 = AbsPair(S_SREG);
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      BIND_GLOBAL(pt0, d0, bind_ullist_var);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
  bind_ullist_var:
#endif
      GONextW();
      END_PREFETCH_W();

      ENDP(pt0);
      ENDD(d0);
      ENDOpRW();

      OpW(unify_struct_write, of);
      CACHE_S();
      READ_IN_S();
      *--SP = Unsigned(S_SREG + 1);
      *--SP = WRITE_MODE;
      /* we continue in write mode */
      BEGD(d0);
      d0 = AbsAppl(H);
      S_SREG[0] = d0;
      S_SREG = H;
      d0 = (CELL) (PREG->u.of.f);
      *S_SREG++ = d0;
      H = S_SREG + PREG->u.of.a;
      PREG = NEXTOP(PREG, of);
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      ENDD(d0);
      GONextW();
      ENDOpW();

      OpRW(unify_struct, of);
      *--SP = Unsigned(SREG + 1);
      *--SP = READ_MODE;
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      START_PREFETCH(of);
      deref_head(d0, ustruct_unk);
    ustruct_nonvar:
      /* we are in read mode */
      if (!IsApplTerm(d0)) {
      FAIL();
      }
      CACHE_S();
      READ_IN_S();
      /* we continue in read mode */
      S_SREG = RepAppl(d0);
      /* just check functor */
      d0 = (CELL) (PREG->u.of.f);
      if (*S_SREG != d0) {
      FAIL();
      }
      PREG = NEXTOP(PREG, of);
      WRITEBACK_S(S_SREG+1);
      ENDCACHE_S();
      GONext();
      END_PREFETCH();

      derefa_body(d0, pt0, ustruct_unk, ustruct_nonvar);
      /* Enter Write mode */
      START_PREFETCH_W(of);
      /* set d1 to be the new structure we are going to create */
      BEGD(d1);
      d1 = AbsAppl(H);
      /* we know the variable must be in the heap */
      BIND_GLOBAL(pt0, d1, bind_ustruct);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_ustruct:
#endif
      /* now, set pt0 to point to the heap where we are going to
       * build our term */
      pt0 = H;
      ENDD(d1);
      /* first, put the functor */
      d0 = (CELL) (PREG->u.of.f);
      *pt0++ = d0;
      H = pt0 + PREG->u.of.a;
      PREG = NEXTOP(PREG, of);
      /* set SREG */
      SREG = pt0;
      /* update H */
      GONextW();
      END_PREFETCH_W();

      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

      OpW(unify_l_struc_write, of);
      BEGD(d0);
      d0 = AbsAppl(H);
      CACHE_S();
      READ_IN_S();
      S_SREG[0] = d0;
      S_SREG = H;
      d0 = (CELL) (PREG->u.of.f);
      *S_SREG++ = d0;
      H = S_SREG + PREG->u.of.a;
      PREG = NEXTOP(PREG, of);
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      ENDD(d0);
      GONextW();
      ENDOpW();

      OpRW(unify_l_struc, of);
      BEGD(d0);
      BEGP(pt0);
      pt0 = SREG;
      d0 = *pt0;
      deref_head(d0, ulstruct_unk);
    ulstruct_nonvar:
      /* we are in read mode */
      START_PREFETCH(of);
      if (!IsApplTerm(d0)) {
      FAIL();
      }
      /* we continue in read mode */
      SREG = RepAppl(d0);
      /* just check functor */
      d0 = (CELL) (PREG->u.of.f);
      if (*SREG++ != d0) {
      FAIL();
      }
      PREG = NEXTOP(PREG, of);
      GONext();
      END_PREFETCH();

      derefa_body(d0, pt0, ulstruct_unk, ulstruct_nonvar);
      /* Enter Write mode */
      /* set d1 to be the new structure we are going to create */
      START_PREFETCH_W(of);
      BEGD(d1);
      d1 = AbsAppl(H);
      /* we know the variable must be in the heap */
      BIND_GLOBAL(pt0, d1, bind_ulstruct);
#ifdef COROUTINING
      DO_TRAIL(pt0, d1);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_ulstruct:
#endif
      /* now, set pt0 to point to the heap where we are going to
       * build our term */
      pt0 = H;
      ENDD(d1);
      /* first, put the functor */
      d0 = (CELL) (PREG->u.of.f);
      *pt0++ = d0;
      H = pt0 + PREG->u.of.a;
      PREG = NEXTOP(PREG, of);
      /* set SREG */
      SREG = pt0;
      /* update H */
      GONextW();
      END_PREFETCH_W();
      ENDP(pt0);

      ENDD(d0);
      ENDOpRW();

/************************************************************************\
* Put Instructions                                           *
\************************************************************************/

      Op(put_x_var, xx);
      BEGP(pt0);
      pt0 = H;
      XREG(PREG->u.xx.xl) = Unsigned(pt0);
      H = pt0 + 1;
      XREG(PREG->u.xx.xr) = Unsigned(pt0);
      PREG = NEXTOP(PREG, xx);
      RESET_VARIABLE(pt0);
      ENDP(pt0);
      GONext();
      ENDOp();

      Op(put_y_var, yx);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yx.y;
      XREG(PREG->u.yx.x) = (CELL) pt0;
      PREG = NEXTOP(PREG, yx);
#if defined(SBA) && defined(FROZEN_STACKS)
      /* We must initialise a shared variable to point to the SBA */
      if (Unsigned((Int)(pt0)-(Int)(H_FZ)) >
        Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
      *pt0 =  (CELL)STACK_TO_SBA(pt0);
      } else
#endif /* SBA && FROZEN_STACKS */
      RESET_VARIABLE(pt0);
      ENDP(pt0);
      GONext();
      ENDOp();

      Op(put_x_val, xx);
      BEGD(d0);
      d0 = XREG(PREG->u.xx.xl);
      XREG(PREG->u.xx.xr) = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, xx);
      GONext();
      ENDOp();

      Op(put_xx_val, xxxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxxx.xl1);
      d1 = XREG(PREG->u.xxxx.xl2);
      XREG(PREG->u.xxxx.xr1) = d0;
      XREG(PREG->u.xxxx.xr2) = d1;
      ENDD(d1);
      ENDD(d0);
      PREG = NEXTOP(PREG, xxxx);
      GONext();
      ENDOp();

      Op(put_y_val, yx);
      BEGD(d0);
      d0 = YREG[PREG->u.yx.y];
#if SBA
      if (d0 == 0) /* new variable */
      XREG(PREG->u.yx.x) = (CELL)(YREG+PREG->u.yx.y);
      else
#endif
      XREG(PREG->u.yx.x) = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, yx);
      GONext();
      ENDOp();

      Op(put_unsafe, yx);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG+PREG->u.yx.y;
      d0 = *pt0;
      deref_head(d0, punsafe_unk);
    punsafe_nonvar:
      XREG(PREG->u.yx.x) = d0;
      PREG = NEXTOP(PREG, yx);
      GONext();

      derefa_body(d0, pt0, punsafe_unk, punsafe_nonvar);
      /* d0 is a variable, check whether we need to globalise it */
      if (pt0 <= H || pt0 >= YREG) {
      /* variable is safe */
      XREG(PREG->u.yx.x) = Unsigned(pt0);
      PREG = NEXTOP(PREG, yx);
      GONext();
      }
      else {
      /* create a new Heap variable and bind our variable to it */
      Bind_Local(pt0, Unsigned(H));
      XREG(PREG->u.yx.x) = (CELL) H;
      RESET_VARIABLE(H);
      H++;
      PREG = NEXTOP(PREG, yx);
      GONext();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(put_atom, xc);
      BEGD(d0);
      d0 = PREG->u.xc.c;
      XREG(PREG->u.xc.x) = d0;
      PREG = NEXTOP(PREG, xc);
      GONext();
      ENDD(d0);
      ENDOp();

      Op(put_list, x);
      CACHE_S();
      READ_IN_S();
      S_SREG = H;
      H += 2;
      BEGD(d0);
      d0 = AbsPair(S_SREG);
      XREG(PREG->u.x.x) = d0;
      PREG = NEXTOP(PREG, x);
      ENDD(d0);
      WRITEBACK_S(S_SREG);
      ENDCACHE_S();
      GONext();
      ENDOp();

      Op(put_struct, xf);
      BEGD(d0);
      d0 = AbsAppl(H);
      XREG(PREG->u.xf.x) = d0;
      d0 = (CELL) (PREG->u.xf.f);
      *H++ = d0;
      SREG = H;
      H += PREG->u.xf.a;
      ENDD(d0);
      PREG = NEXTOP(PREG, xf);
      GONext();
      ENDOp();

/************************************************************************\
*     Write Instructions                                    *
\************************************************************************/

      Op(write_x_var, x);
      XREG(PREG->u.x.x) = Unsigned(SREG);
      PREG = NEXTOP(PREG, x);
      RESET_VARIABLE(SREG);
      SREG++;
      GONext();
      ENDOp();

      Op(write_void, e);
      PREG = NEXTOP(PREG, e);
      RESET_VARIABLE(SREG);
      SREG++;
      GONext();
      ENDOp();

      Op(write_n_voids, s);
      BEGD(d0);
      d0 = PREG->u.s.s;
      PREG = NEXTOP(PREG, s);
      for (; d0 > 0; d0--) {
      RESET_VARIABLE(SREG);
      SREG++;
      }
      ENDD(d0);
      GONext();
      ENDOp();

      Op(write_y_var, y);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.y.y,Unsigned(SREG));
#else
      YREG[PREG->u.y.y] = Unsigned(SREG);
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, y);
      RESET_VARIABLE(SREG);
      SREG++;
      GONext();
      ENDOp();

      Op(write_x_val, x);
      BEGD(d0);
      d0 = XREG(PREG->u.x.x);
      *SREG++ = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, x);
      GONext();
      ENDOp();

      Op(write_x_loc, x);
      BEGD(d0);
      d0 = XREG(PREG->u.x.x);
      PREG = NEXTOP(PREG, x);
      deref_head(d0, w_x_unk);
    w_x_bound:
      *SREG++ = d0;
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, w_x_unk, w_x_bound);
#if defined(SBA) && defined(FROZEN_STACKS)
      if (pt0 > H && pt0<(CELL *)B_FZ) {
#else
      if (pt0 > H) {
#endif /* SBA && FROZEN_STACKS */
      /* local variable: let us bind it to the list */
#ifdef FROZEN_STACKS  /* TRAIL */
      Bind_Local(pt0, Unsigned(SREG));
#else
      TRAIL_LOCAL(pt0, Unsigned(SREG));
      *pt0 = Unsigned(SREG);
#endif /* FROZEN_STACKS */
      RESET_VARIABLE(SREG);
      SREG++;
      GONext();
      }
      else {
      *SREG++ = Unsigned(pt0);
      GONext();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(write_y_val, y);
      BEGD(d0);
      d0 = YREG[PREG->u.y.y];
#if SBA
      if (d0 == 0) /* new variable */
      *SREG++ = (CELL)(YREG+PREG->u.y.y);
      else
#endif
      *SREG++ = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, y);
      GONext();
      ENDOp();

      Op(write_y_loc, y);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG+PREG->u.y.y;
      d0 = *pt0;
      deref_head(d0, w_y_unk);
    w_y_bound:
      PREG = NEXTOP(PREG, y);
      *SREG++ = d0;
      GONext();

      derefa_body(d0, pt0, w_y_unk, w_y_bound);
#if defined(SBA) && defined(FROZEN_STACKS)
      if (pt0 > H && pt0<(CELL *)B_FZ) {
#else
      if (pt0 > H) {
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, y);
      /* local variable: let us bind it to the list */
#ifdef FROZEN_STACKS
      Bind_Local(pt0, Unsigned(SREG));
#else
      *pt0 = Unsigned(SREG);
      TRAIL_LOCAL(pt0, Unsigned(SREG));
#endif /* FROZEN_STACKS */
      RESET_VARIABLE(SREG);
      SREG++;
      GONext();
      }
      else {
      PREG = NEXTOP(PREG, y);
      *SREG++ = Unsigned(pt0);
      GONext();
      }
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(write_atom, c);
      BEGD(d0);
      d0 = PREG->u.c.c;
      *SREG++ = d0;
      ENDD(d0);
      PREG = NEXTOP(PREG, c);
      GONext();
      ENDOp();

      Op(write_n_atoms, sc);
      BEGD(d0);
      BEGD(d1);
      d0 = PREG->u.sc.s;
      d1 = PREG->u.sc.c;
      for (; d0 > 0; d0--)
      *SREG++ = d1;
      ENDD(d1);
      ENDD(d0);
      PREG = NEXTOP(PREG, sc);
      GONext();
      ENDOp();

      Op(write_list, e);
      BEGD(d0);
      d0 = AbsPair(H);
      *SREG++ = d0;
      /* I will not actually store the mode in the stack */
      SP[-1] = Unsigned(SREG);
      SP[-2] = 1;       /* Put instructions follow the main stream */
      SP -= 2;
      SREG = H;
      H += 2;
      ENDD(d0);
      PREG = NEXTOP(PREG, e);
      GONext();
      ENDOp();

      Op(write_l_list, e);
      ALWAYS_START_PREFETCH(e);
      PREG = NEXTOP(PREG, e);
      BEGD(d0);
      CACHE_S();
      READ_IN_S();
      d0 = AbsPair(H);
      *S_SREG = d0;
      WRITEBACK_S(H);
      H += 2;
      ENDCACHE_S();
      ENDD(d0);
      ALWAYS_END_PREFETCH();
      GONext();
      ENDOp();

      Op(write_struct, f);
      BEGD(d0);
      d0 = AbsAppl(H);
      *SREG++ = d0;
      SP[-1] = Unsigned(SREG);
      SP[-2] = 1;       /* Put instructions follow the main stream */
      SP -= 2;
      d0 = (CELL) (PREG->u.f.f);
      *H++ = d0;
      ENDD(d0);
      BEGD(d0);
      d0 = PREG->u.f.a;
      PREG = NEXTOP(PREG, f);
      SREG = H;
      H += d0;
      ENDD(d0);
      GONext();
      ENDOp();

      Op(write_l_struc, f);
      BEGD(d0);
      d0 = AbsAppl(H);
      *SREG = d0;
      d0 = (CELL) (PREG->u.f.f);
      *H++ = d0;
      SREG = H;
      ENDD(d0);
      BEGD(d0);
      d0 = PREG->u.f.a;
      PREG = NEXTOP(PREG, f);
      H += d0;
      ENDD(d0);
      GONext();
      ENDOp();

/************************************************************************\
*   Save last unified struct or list                              *
\************************************************************************/

/* vitor: I think I should kill these two instructions, by expanding the
 * othe instructions.
 */

      OpW(save_pair_x_write, ox);
      XREG(PREG->u.ox.x) = AbsPair(SREG);
      PREG = NEXTOP(PREG, ox);
      GONextW();
      ENDOpW();

      Op(save_pair_x, ox);
      XREG(PREG->u.ox.x) = AbsPair(SREG);
      PREG = NEXTOP(PREG, ox);
      GONext();
      ENDOp();

      OpW(save_pair_y_write, oy);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.oy.y,AbsPair(SREG));
#else
      YREG[PREG->u.oy.y] = AbsPair(SREG);
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, oy);
      GONextW();
      ENDOpW();

      Op(save_pair_y, oy);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.oy.y,AbsPair(SREG));
#else
      YREG[PREG->u.oy.y] = AbsPair(SREG);
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, oy);
      GONext();
      ENDOp();

      OpW(save_appl_x_write, ox);
      XREG(PREG->u.ox.x) = AbsAppl(SREG - 1);
      PREG = NEXTOP(PREG, ox);
      GONextW();
      ENDOpW();

      Op(save_appl_x, ox);
      XREG(PREG->u.ox.x) = AbsAppl(SREG - 1);
      PREG = NEXTOP(PREG, ox);
      GONext();
      ENDOp();

      OpW(save_appl_y_write, oy);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.oy.y,AbsAppl(SREG-1));
#else
      YREG[PREG->u.oy.y] = AbsAppl(SREG - 1);
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, oy);
      GONextW();
      ENDOpW();

      Op(save_appl_y, oy);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(YREG+PREG->u.oy.y,AbsAppl(SREG-1));
#else
      YREG[PREG->u.oy.y] = AbsAppl(SREG - 1);
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, oy);
      GONext();
      ENDOp();

/************************************************************************\
*   Instructions for implemeting 'or;'                             *
\************************************************************************/

      BOp(jump, l);
      PREG = PREG->u.l.l;
      JMPNext();
      ENDBOp();

      /* This instruction is called when the previous goal
       was interrupted when waking up goals
      */     
      BOp(move_back, l);
      PREG = (yamop *)(((char *)PREG)-(Int)(NEXTOP((yamop *)NULL,sla)));
      JMPNext();
      ENDBOp();

      /* This instruction is called when the previous goal
       was interrupted when waking up goals
      */     
      BOp(skip, l);
      PREG = NEXTOP(PREG,l);
      JMPNext();
      ENDBOp();

      Op(either, sla);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      low_level_trace(try_or, (PredEntry *)PREG, NULL);
      }
#endif
#ifdef COROUTINING
      CACHE_Y_AS_ENV(YREG);
      check_stack(NoStackEither, H);
      ENDCACHE_Y_AS_ENV();
      either_notest:
#endif
      BEGD(d0);
      /* Try to preserve the environment */
      d0 = PREG->u.sla.s;
      BEGCHO(pt1);
      pt1 = (choiceptr) ((char *) YREG + (yslot) d0);
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (pt1 > top_b || pt1 < (choiceptr)H) pt1 = top_b;
#else
      if (pt1 > top_b) pt1 = top_b;
#endif /* SBA */
      }
#else
      if (pt1 > B) {
      pt1 = B;
      }
#endif /* FROZEN_STACKS */
      pt1 = (choiceptr)(((CELL *) pt1)-1);
      *(CELL **) pt1 = YREG;
      store_yaam_regs_for_either(PREG->u.sla.sla_u.l, PREG);
      SREG = (CELL *) (B = pt1);
#ifdef YAPOR
      SCH_set_load(pt1);
#endif      /* YAPOR */
      SET_BB(pt1);
      ENDCHO(pt1);
      /* skip the current instruction plus the next one */
      PREG = NEXTOP(NEXTOP(PREG, sla),l);
      GONext();
      ENDD(d0);
      ENDOp();

      Op(or_else, sla);
      H = HBREG = PROTECT_FROZEN_H(B);
      ENV = B->cp_env;
      B->cp_cp = PREG;
#ifdef DEPTH_LIMIT
      DEPTH = B->cp_depth;
#endif      /* DEPTH_LIMIT */
      SET_BB(PROTECT_FROZEN_B(B));
#ifdef YAPOR
      if (SCH_top_shared_cp(B)) {
      SCH_new_alternative(PREG, PREG->u.sla.sla_u.l);
      } else
#endif      /* YAPOR */
      B->cp_ap = PREG->u.sla.sla_u.l;
      PREG = NEXTOP(PREG, sla);
      YREG = (CELL *) B->cp_a1;
      GONext();
      ENDOp();

#ifdef YAPOR
      Op(or_last, sla);
#else
      Op(or_last, p);
#endif      /* YAPOR */
      BEGCHO(pt0);
      pt0 = B;
#ifdef YAPOR
      if (SCH_top_shared_cp(B)) {
      H = HBREG = PROTECT_FROZEN_H(pt0);
      YREG = (CELL *) pt0->cp_a1;
      ENV = pt0->cp_env;
#ifdef DEPTH_LIMIT
      DEPTH = pt0->cp_depth;
#endif      /* DEPTH_LIMIT */
        SCH_new_alternative(PREG, NULL);
      }
      else
#endif      /* YAPOR */
      {
      B = pt0->cp_b;
      H = PROTECT_FROZEN_H(pt0);
      YREG = (CELL *) pt0->cp_a1;
      ENV = pt0->cp_env;
#ifdef DEPTH_LIMIT
      DEPTH = pt0->cp_depth;
#endif      /* DEPTH_LIMIT */
      HBREG = PROTECT_FROZEN_H(B);
      }
#ifdef YAPOR
      PREG = NEXTOP(PREG, sla);
#else
      PREG = NEXTOP(PREG, p);
#endif      /* YAPOR */
      SET_BB(PROTECT_FROZEN_B(B));
      GONext();
      ENDCHO(pt0);
      ENDOp();

/************************************************************************\
*     Pop operations                                         *
\************************************************************************/

      OpRW(pop_n, s);
      /* write mode might have been called from read mode */
      BEGD(d0);
      d0 = PREG->u.os.s;
      SP = (CELL *) (((char *) SP) + d0);
      ENDD(d0);
      BEGD(d0);
      d0 = SP[0];
      if (d0) {
      START_PREFETCH(s);
      SREG = (CELL *) (SP[1]);
      SP += 2;
      PREG = NEXTOP(PREG, s);
      GONext();
      END_PREFETCH();
      }
      else {
      START_PREFETCH_W(s);
      SREG = (CELL *) (SP[1]);
      SP += 2;
      PREG = NEXTOP(PREG, s);
      GONextW();
      END_PREFETCH_W();
      }
      ENDD(d0);
      ENDOpRW();

      OpRW(pop, e);
      BEGD(d0);
      d0 = SP[0];
      SREG = (CELL *) (SP[1]);
      SP += 2;
      if (d0) {
      START_PREFETCH(e);
      PREG = NEXTOP(PREG, e);
      GONext();
      END_PREFETCH();
      }
      else {
      START_PREFETCH_W(e);
      PREG = NEXTOP(PREG, e);
      GONextW();
      END_PREFETCH_W();
      }
      ENDD(d0);
      ENDOpRW();

/************************************************************************\
*     Call C predicates instructions                               *
\************************************************************************/

      BOp(call_cpred, sla);
     

      if (!(PREG->u.sla.sla_u.p->PredFlags & (SafePredFlag|HiddenPredFlag))) {
      CACHE_Y_AS_ENV(YREG);
      check_stack(NoStackCall, H);
      ENDCACHE_Y_AS_ENV();
      }
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);

#ifdef SBA
      if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *)top_b;
#else
      if (YREG > (CELL *) top_b) ASP = (CELL *)top_b;
#endif /* SBA */
      else ASP = (CELL *)(((char *)YREG) +  PREG->u.sla.s);
      }
#else
      if (YREG > (CELL *) B) {
      ASP = (CELL *) B;
      } else {
      ASP = (CELL *) (((char *) YREG) + PREG->u.sla.s);
      }
      /* for slots to work */
#endif /* FROZEN_STACKS */
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,PREG->u.sla.sla_u.p,XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      CPredicate f = PREG->u.sla.sla_u.p->cs.f_code;
      PREG = NEXTOP(PREG, sla);
      saveregs();
      d0 = (f)();
      setregs();
      if (!d0) {
      FAIL();
      }
      CACHE_A1();
      ENDD(d0);
      JMPNext();
      ENDBOp();
      
      /* Like previous, the only difference is that we do not */
      /* trust the C-function we are calling and hence we must */
      /* guarantee that *all* machine registers are saved and */
      /* restored */
      BOp(call_usercpred, sla);
      CACHE_Y_AS_ENV(YREG);
      check_stack(NoStackCall, H);
      ENDCACHE_Y_AS_ENV();
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *) top_b;
#else
      if (YREG > (CELL *) top_b) ASP = (CELL *) top_b;
#endif /* SBA */
      else ASP = (CELL *)(((char *)YREG) +  PREG->u.sla.s);
      }
#else
      if (YREG > (CELL *) B)
      ASP = (CELL *) B;
      else {
      ASP = (CELL *) (((char *) YREG) + PREG->u.sla.s);
      }
      /* for slots to work */
      Yap_StartSlots();
      Yap_PrologMode = UserCCallMode;
#endif /* FROZEN_STACKS */
      {
      PredEntry *p = PREG->u.sla.sla_u.p;
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
        low_level_trace(enter_pred,p,XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      PREG = NEXTOP(PREG, sla);
      saveregs();
      save_machine_regs();

      SREG = (CELL *) YAP_Execute(p, p->cs.f_code);
      EX = 0L;
      }

      restore_machine_regs();
      setregs();
      Yap_PrologMode = UserMode;
      if (!SREG) {
      FAIL();
      }
      JMPNext();
      ENDBOp();

      BOp(call_c_wfail, sdl);
#ifdef FROZEN_STACKS
      { 
      choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
      if (YREG > (CELL *) top_b || YREG < H) ASP = (CELL *) top_b;
#else
      if (YREG > (CELL *) top_b) ASP = (CELL *) top_b;
#endif /* SBA */
      else {
        BEGD(d0);
        d0 = PREG->u.sdl.s;
        ASP = ((CELL *)YREG) + d0;
        ENDD(d0);
      }
      }
#else
      if (YREG > (CELL *) B)
      ASP = (CELL *) B;
      else {
      BEGD(d0);
      d0 = PREG->u.sdl.s;
      ASP = ((CELL *) YREG) + d0;
      ENDD(d0);
      }
#endif /* FROZEN_STACKS */
      {
      CPredicate f = PREG->u.sdl.p->cs.f_code;
      saveregs();
      SREG = (CELL *)((f)());
      setregs();
      }
      if (!SREG)
      PREG = PREG->u.sdl.l;
      else
      PREG = NEXTOP(PREG, sdl);
      CACHE_A1();
      JMPNext();
      ENDBOp();

      BOp(try_c, lds);
#ifdef YAPOR
      CUT_wait_leftmost();
#endif /* YAPOR */
      CACHE_Y(YREG);
#ifdef CUT_C
      /* Alocate space for the cut_c structure*/
      CUT_C_PUSH(NEXTOP(NEXTOP(PREG,lds),lds),S_YREG);
#endif  
      S_YREG = S_YREG - PREG->u.lds.extra;
      store_args(PREG->u.lds.s);
      store_yaam_regs(NEXTOP(PREG, lds), 0);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();

    TRYCC:
      ASP = (CELL *)B;
      {
      CPredicate f = (CPredicate)(PREG->u.lds.f);
      saveregs();
      SREG = (CELL *) ((f) ());
      /* This last instruction changes B B*/
#ifdef CUT_C
      while (POP_CHOICE_POINT(B)){ 
        cut_c_pop();
      }
#endif 
      }
      setregs();
      if (!SREG) {
#ifdef CUT_C
      /* Removes the cut functions from the stack
       without executing them because we have fail 
       and not cuted the predicate*/
      while(POP_CHOICE_POINT(B))
        cut_c_pop();
#endif 
      FAIL();
      }
      if ((CELL *) B == YREG && ASP != (CELL *) B) {
      /* as Luis says, the predicate that did the try C might
       * have left some data on the stack. We should preserve
       * it, unless the builtin also did cut */
      YREG = ASP;
      HBREG = PROTECT_FROZEN_H(B);
      SET_BB(B);
      }
      PREG = CPREG;
      YREG = ENV;
      JMPNext();
      ENDBOp();

      BOp(retry_c, lds);
#ifdef YAPOR
      CUT_wait_leftmost();
#endif /* YAPOR */
      CACHE_Y(B);
      CPREG = B_YREG->cp_cp;
      ENV = B_YREG->cp_env;
      H = PROTECT_FROZEN_H(B);
#ifdef DEPTH_LIMIT
      DEPTH =B->cp_depth;
#endif
      HBREG = H;
      restore_args(PREG->u.lds.s);
      ENDCACHE_Y();
      goto TRYCC;
      ENDBOp();

#ifdef CUT_C
      BOp(cut_c, lds);
      /*This is a phantom instruction. This is not executed by the WAM*/
#ifdef DEBUG
      /*If WAM executes this instruction, probably there's an error
       when we put this instruction, cut_c, after retry_c*/
      printf ("ERROR: Should not print this message FILE: absmi.c %d\n",__LINE__);
#endif /*DEBUG*/
      ENDBOp();
#endif

      BOp(try_userc, lds);
#ifdef YAPOR
      CUT_wait_leftmost();
#endif /* YAPOR */
      CACHE_Y(YREG);
#ifdef CUT_C
      /* Alocate space for the cut_c structure*/
      CUT_C_PUSH(NEXTOP(NEXTOP(PREG,lds),lds),S_YREG);
#endif
      S_YREG = S_YREG - PREG->u.lds.extra;
      store_args(PREG->u.lds.s);
      store_yaam_regs(NEXTOP(PREG, lds), 0);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif
      SET_BB(B_YREG);
      ENDCACHE_Y();

    TRYUSERCC:
      Yap_PrologMode = UserCCallMode;
      ASP = YENV;
      saveregs();
      save_machine_regs();
      SREG = (CELL *) YAP_Execute(PREG->u.lds.p, (CPredicate)(PREG->u.lds.f));
      EX = 0L;
      restore_machine_regs();
      setregs();
      Yap_PrologMode = UserMode;
      if (!SREG) {
#ifdef CUT_C
      /* Removes the cut functions from the stack
       without executing them because we have fail 
       and not cuted the predicate*/
      while(POP_CHOICE_POINT(B))
        cut_c_pop();
#endif 
      FAIL();
      }
      if ((CELL *) B == YREG && ASP != (CELL *) B) {
      /* as Luis says, the predicate that did the try C might
       * have left some data on the stack. We should preserve
       * it, unless the builtin also did cut */
      YREG = ASP;
      HBREG = PROTECT_FROZEN_H(B);
      }
      PREG = CPREG;
      YREG = ENV;
      CACHE_A1();
      JMPNext();
      ENDBOp();

      BOp(retry_userc, lds);
#ifdef YAPOR
      CUT_wait_leftmost();
#endif /* YAPOR */
      CACHE_Y(B);
      CPREG = B_YREG->cp_cp;
      ENV = B_YREG->cp_env;
      H = PROTECT_FROZEN_H(B);
#ifdef DEPTH_LIMIT
      DEPTH =B->cp_depth;
#endif
      HBREG = H;
      restore_args(PREG->u.lds.s);
      ENDCACHE_Y();
      goto TRYUSERCC;
      ENDBOp();

#ifdef CUT_C
      BOp(cut_userc, lds);
      /*This is a phantom instruction. This is not executed by the WAM*/
#ifdef DEBUG
      /*If WAM executes this instruction, probably there's an error
       when we put this instruction, cut_userc, after retry_userc*/
      printf ("ERROR: Should not print this message FILE: absmi.c %d\n",__LINE__);
#endif /*DEBUG*/
      ENDBOp();
#endif


/************************************************************************\
*     support instructions                                   *
\************************************************************************/

      BOp(index_pred, e);
      {
      PredEntry *ap = PredFromDefCode(PREG);
      WRITE_LOCK(ap->PRWLock);
#if defined(YAPOR) || defined(THREADS)
      /*
      we do not lock access to the predicate,
      we must take extra care here
      */
      if (ap->OpcodeOfPred != INDEX_OPCODE) {
        /* someone was here before we were */
        PREG = ap->CodeOfPred;
        /* for profiler */
        save_pc();
        WRITE_UNLOCK(ap->PRWLock);
        JMPNext();
      }
#endif
      /* update ASP before calling IPred */
      ASP = YREG+E_CB;
      if (ASP > (CELL *) PROTECT_FROZEN_B(B)) {
        ASP = (CELL *) PROTECT_FROZEN_B(B);
      }
      saveregs();
      Yap_IPred(ap, 0);
      /* IPred can generate errors, it thus must get rid of the lock itself */
      setregs();
      CACHE_A1();
      PREG = ap->CodeOfPred;
      /* for profiler */
      save_pc();
      WRITE_UNLOCK(ap->PRWLock);
      }
      JMPNext();
      ENDBOp();

#if THREADS
      BOp(thread_local, e);
      {
      PredEntry *ap = PredFromDefCode(PREG);
      ap = Yap_GetThreadPred(ap);
      PREG = ap->CodeOfPred;
      /* for profiler */
      save_pc();
      }
      JMPNext();
      ENDBOp();
#endif

      BOp(expand_index, e);
      {
      PredEntry *pe = PredFromExpandCode(PREG);
      yamop *pt0;

      /* update ASP before calling IPred */
      ASP = YREG+E_CB;
      if (ASP > (CELL *) PROTECT_FROZEN_B(B)) {
        ASP = (CELL *) PROTECT_FROZEN_B(B);
      }
#if defined(YAPOR) || defined(THREADS)
      if (PP == NULL) {
        READ_LOCK(pe->PRWLock);
        PP = pe;
      }
      LOCK(pe->PELock);
      if (!same_lu_block(PREG_ADDR, PREG)) {
        PREG = *PREG_ADDR;
        if (pe->PredFlags & (ThreadLocalPredFlag|LogUpdatePredFlag)) {
          READ_UNLOCK(pe->PRWLock);
          PP = NULL;
        }
        UNLOCK(pe->PELock);
        JMPNext();
      }
#endif
      saveregs();
 {
   static yamop *opppp;
   opppp= PREG;
 }
      pt0 = Yap_ExpandIndex(pe, 0);
      /* restart index */
      setregs();
      UNLOCK(pe->PELock);
      PREG = pt0;
#if defined(YAPOR) || defined(THREADS)
      if (pe->PredFlags & (ThreadLocalPredFlag|LogUpdatePredFlag)) {
        READ_UNLOCK(pe->PRWLock);
        PP = NULL;
      }
#endif
      JMPNext();
      }
      ENDBOp();

      BOp(expand_clauses, sp);
      {
      PredEntry *pe = PREG->u.sp.p;
      yamop *pt0;

      /* update ASP before calling IPred */
      ASP = YREG+E_CB;
      if (ASP > (CELL *) PROTECT_FROZEN_B(B)) {
        ASP = (CELL *) PROTECT_FROZEN_B(B);
      }
#if defined(YAPOR) || defined(THREADS)
      if (PP == NULL) {
        READ_LOCK(pe->PRWLock);
        PP = pe;
      }
      LOCK(pe->PELock);
      if (!same_lu_block(PREG_ADDR, PREG)) {
        PREG = *PREG_ADDR;
        if (pe->PredFlags & (ThreadLocalPredFlag|LogUpdatePredFlag)) {
          READ_UNLOCK(pe->PRWLock);
          PP = NULL;
        }
        UNLOCK(pe->PELock);
        JMPNext();
      }
#endif
      saveregs();
      pt0 = Yap_ExpandIndex(pe, 0);
      /* restart index */
      setregs();
      UNLOCK(pe->PELock);
      PREG = pt0;
#if defined(YAPOR) || defined(THREADS)
      if (pe->PredFlags & (ThreadLocalPredFlag|LogUpdatePredFlag)) {
        READ_UNLOCK(pe->PRWLock);
        PP = NULL;
      }
#endif
      JMPNext();
      }
      ENDBOp();

      BOp(undef_p, e);
      /* save S for module name */
      { 
      PredEntry *pe = PredFromDefCode(PREG);
      BEGD(d0);
      READ_LOCK(pe->PRWLock);
      /* avoid trouble with undefined dynamic procedures */
      if (pe->PredFlags & (DynamicPredFlag|LogUpdatePredFlag)) {
        READ_UNLOCK(pe->PRWLock);
        FAIL();
      }
      d0 = pe->ArityOfPE;
      READ_UNLOCK(pe->PRWLock);
      if (d0 == 0) {
        H[1] = MkAtomTerm((Atom)(pe->FunctorOfPred));
      }
      else {
        H[d0 + 2] = AbsAppl(H);
        *H = (CELL) pe->FunctorOfPred;
        H++;
        BEGP(pt1);
        pt1 = XREGS + 1;
        for (; d0 > 0; --d0) {
          BEGD(d1);
          BEGP(pt0);
          pt0 = pt1++;
          d1 = *pt0;
          deref_head(d1, undef_unk);
        undef_nonvar:
          /* just copy it to the heap */
          *H++ = d1;
          continue;

          derefa_body(d1, pt0, undef_unk, undef_nonvar);
          if (pt0 <= H) {
            /* variable is safe */
            *H++ = (CELL)pt0;
          } else {
            /* bind it, in case it is a local variable */
            d1 = Unsigned(H);
            RESET_VARIABLE(H);
            H += 1;
            Bind_Local(pt0, d1);
          }
          ENDP(pt0);
          ENDD(d1);
        }
        ENDP(pt1);
      }
      ENDD(d0);
      H[0] = Yap_Module_Name(pe);
      ARG1 = (Term) AbsPair(H);
      H += 2;
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,UndefCode,XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      }

      PREG = UndefCode->CodeOfPred;
      /* for profiler */
      save_pc();
      CACHE_A1();
      JMPNext();
      ENDBOp();

      BOp(spy_pred, e);
    dospy:
      {
      PredEntry *pe = PredFromDefCode(PREG);
      BEGD(d0);
      d0 = pe->ArityOfPE;
      /* save S for ModuleName */
      if (d0 == 0) {
        H[1] = MkAtomTerm((Atom)(pe->FunctorOfPred));
      } else {
        *H = (CELL) pe->FunctorOfPred;
        H[d0 + 2] = AbsAppl(H);
        H++;
        BEGP(pt1);
        pt1 = XREGS + 1;
        for (; d0 > 0; --d0) {
          BEGD(d1);
          BEGP(pt0);
          pt0 = pt1++;
          d1 = *pt0;
          deref_head(d1, dospy_unk);
        dospy_nonvar:
          /* just copy it to the heap */
          *H++ = d1;
          continue;
          
          derefa_body(d1, pt0, dospy_unk, dospy_nonvar);
          if (pt0 <= H) {
            /* variable is safe */
            *H++ = (CELL)pt0;
          } else {
            /* bind it, in case it is a local variable */
            d1 = Unsigned(H);
            RESET_VARIABLE(H);
            H += 1;
            Bind_Local(pt0, d1);
          }
          ENDP(pt0);
          ENDD(d1);
        }
        ENDP(pt1);
      }
      ENDD(d0);
      H[0] = Yap_Module_Name(pe);
      }
      ARG1 = (Term) AbsPair(H);
      H += 2;
      {
      PredEntry *pt0;
      pt0 = SpyCode;
      P_before_spy = PREG;
      PREG = pt0->CodeOfPred;
      /* for profiler */
      save_pc();
      CACHE_A1();
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
        low_level_trace(enter_pred,pt0,XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      }
      JMPNext();
      ENDBOp();


/************************************************************************\
*     Try / Retry / Trust for main indexing blocks                *
\************************************************************************/

      BOp(try_clause, ld);
      check_trail(TR);
      CACHE_Y(YREG);
      /* Point AP to the code that follows this instruction */
      store_at_least_one_arg(PREG->u.ld.s);
      store_yaam_regs(NEXTOP(PREG, ld), 0);
      PREG = PREG->u.ld.d;
      set_cut(S_YREG, B);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(try_clause2, l);
      check_trail(TR);
      CACHE_Y(YREG);
      /* Point AP to the code that follows this instruction */
      {
      register CELL x2 = ARG2;
      register CELL x1 = ARG1;

      store_yaam_regs(NEXTOP(PREG, l), 2);
      B_YREG->cp_a1 = x1;
      B_YREG->cp_a2 = x2;
      }
      PREG = PREG->u.l.l;
      set_cut(S_YREG, B);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(try_clause3, l);
      check_trail(TR);
      CACHE_Y(YREG);
      /* Point AP to the code that follows this instruction */
      {
      store_yaam_regs(NEXTOP(PREG, l), 3);
      B_YREG->cp_a1 = ARG1;
      B_YREG->cp_a2 = ARG2;
      B_YREG->cp_a3 = ARG3;
      }
      PREG = PREG->u.l.l;
      set_cut(S_YREG, B);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(try_clause4, l);
      check_trail(TR);
      CACHE_Y(YREG);
      /* Point AP to the code that follows this instruction */
      {
      store_yaam_regs(NEXTOP(PREG, l), 4);
      B_YREG->cp_a1 = ARG1;
      B_YREG->cp_a2 = ARG2;
      B_YREG->cp_a3 = ARG3;
      B_YREG->cp_a4 = ARG4;
      }
      PREG = PREG->u.l.l;
      set_cut(S_YREG, B);
      B = B_YREG;
#ifdef YAPOR
      SCH_set_load(B_YREG);
#endif      /* YAPOR */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(retry, ld);
      CACHE_Y(B);
      restore_yaam_regs(NEXTOP(PREG, ld));
      restore_at_least_one_arg(PREG->u.ld.s);
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      PREG = PREG->u.ld.d;
      JMPNext();
      ENDBOp();

      BOp(retry2, l);
      CACHE_Y(B);
      restore_yaam_regs(NEXTOP(PREG, l));
      PREG = PREG->u.l.l;
      ARG1 = B_YREG->cp_a1;
      ARG2 = B_YREG->cp_a2;
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(retry3, l);
      CACHE_Y(B);
      restore_yaam_regs(NEXTOP(PREG, l));
      PREG = PREG->u.l.l;
      ARG1 = B_YREG->cp_a1;
      ARG2 = B_YREG->cp_a2;
      ARG3 = B_YREG->cp_a3;
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(retry4, l);
      CACHE_Y(B);
      restore_yaam_regs(NEXTOP(PREG, l));
      PREG = PREG->u.l.l;
      ARG1 = B_YREG->cp_a1;
      ARG2 = B_YREG->cp_a2;
      ARG3 = B_YREG->cp_a3;
      ARG4 = B_YREG->cp_a4;
#ifdef FROZEN_STACKS
      S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
      set_cut(S_YREG, B->cp_b);
#else
      set_cut(S_YREG, B_YREG->cp_b);
#endif /* FROZEN_STACKS */
      SET_BB(B_YREG);
      ENDCACHE_Y();
      JMPNext();
      ENDBOp();

      BOp(trust, ld);
      CACHE_Y(B);
#ifdef YAPOR
      if (SCH_top_shared_cp(B)) {
      SCH_last_alternative(PREG, B_YREG);
      restore_at_least_one_arg(PREG->u.ld.s);
#ifdef FROZEN_STACKS
        S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B->cp_b);
      }
      else
#endif      /* YAPOR */
      {
      pop_yaam_regs();
      pop_at_least_one_arg(PREG->u.ld.s);
#ifdef FROZEN_STACKS
        S_YREG = (CELL *) PROTECT_FROZEN_B(B_YREG);
#endif /* FROZEN_STACKS */
      set_cut(S_YREG, B);
      }
      SET_BB(B_YREG);
      ENDCACHE_Y();
      PREG = PREG->u.ld.d;
      JMPNext();
      ENDBOp();

      BOp(try_in, l);
      B->cp_ap = NEXTOP(PREG, l);
      PREG = PREG->u.l.l;
      JMPNext();
      ENDBOp();



/************************************************************************\
*     Indexing in ARG1                                *
\************************************************************************/

      BOp(switch_on_type, llll);
      BEGD(d0);
      d0 = CACHED_A1();
      deref_head(d0, swt_unk);
      /* nonvar */
    swt_nvar:
      if (IsPairTerm(d0)) {
      /* pair */
      SREG = RepPair(d0);
      copy_jmp_address(PREG->u.llll.l1);
      PREG = PREG->u.llll.l1;
      JMPNext();
      }
      else if (!IsApplTerm(d0)) {
      /* constant */
      copy_jmp_address(PREG->u.llll.l2);
      PREG = PREG->u.llll.l2;
      I_R = d0;
      JMPNext();
      }
      else {
      /* appl */
      copy_jmp_address(PREG->u.llll.l3);
      PREG = PREG->u.llll.l3;
      SREG = RepAppl(d0);
      JMPNext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, swt_unk, swt_nvar);
      /* variable */
      copy_jmp_address(PREG->u.llll.l4);
      PREG = PREG->u.llll.l4;
      JMPNext();
      ENDP(pt0);
      ENDD(d0);
      ENDBOp();

      /* specialised case where the arguments may be:
       * a list;
       * the empty list;
       * some other atom;
       * a variable;
       * 
       */
      BOp(switch_list_nl, ollll);
      ALWAYS_LOOKAHEAD(PREG->u.ollll.pop);
      BEGD(d0);
      d0 = CACHED_A1();
#if UNIQUE_TAG_FOR_PAIRS
      deref_list_head(d0, swlnl_unk_p);
      swlnl_list_p:
      {
#else
      deref_head(d0, swlnl_unk_p);
      /* non variable */
      swlnl_nvar_p:
      if (IsPairTerm(d0)) {
        /* pair */
#endif
        copy_jmp_address(PREG->u.ollll.l1);
        PREG = PREG->u.ollll.l1;
        SREG = RepPair(d0);
        ALWAYS_GONext();
      }
#if UNIQUE_TAG_FOR_PAIRS
      swlnl_nlist_p:
#endif
      if (d0 == TermNil) {
        /* empty list */
        PREG = PREG->u.ollll.l2;
        JMPNext();
      }
      else {
        /* appl or constant */
        if (IsApplTerm(d0)) {
          copy_jmp_address(PREG->u.ollll.l3);
          PREG = PREG->u.ollll.l3;
          SREG = RepAppl(d0);
          JMPNext();
        } else {
          copy_jmp_address(PREG->u.ollll.l3);
          PREG = PREG->u.ollll.l3;
          I_R = d0;
          JMPNext();
        }
      }

      BEGP(pt0);
#if UNIQUE_TAG_FOR_PAIRS
      swlnl_unk_p:
      deref_list_body(d0, pt0, swlnl_list_p, swlnl_nlist_p);
#else
      deref_body(d0, pt0, swlnl_unk_p, swlnl_nvar_p);
#endif
      ENDP(pt0);
      /* variable */
      copy_jmp_address(PREG->u.ollll.l4);
      PREG = PREG->u.ollll.l4;
      JMPNext();
      ENDD(d0);
      }
      ENDBOp();

      BOp(switch_on_arg_type, xllll);
      BEGD(d0);
      d0 = XREG(PREG->u.xllll.x);
      deref_head(d0, arg_swt_unk);
      /* nonvar */
    arg_swt_nvar:
      if (IsPairTerm(d0)) {
      /* pair */
      copy_jmp_address(PREG->u.xllll.l1);
      PREG = PREG->u.xllll.l1;
      SREG = RepPair(d0);
      JMPNext();
      }
      else if (!IsApplTerm(d0)) {
      /* constant */
      copy_jmp_address(PREG->u.xllll.l2);
      PREG = PREG->u.xllll.l2;
      I_R = d0;
      JMPNext();
      }
      else {
      /* appl */
      copy_jmp_address(PREG->u.xllll.l3);
      PREG = PREG->u.xllll.l3;
      SREG = RepAppl(d0);
      JMPNext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, arg_swt_unk, arg_swt_nvar);
      /* variable */
      copy_jmp_address(PREG->u.xllll.l4);
      PREG = PREG->u.xllll.l4;
      JMPNext();
      ENDP(pt0);
      ENDD(d0);
      ENDBOp();

      BOp(switch_on_sub_arg_type, sllll);
      BEGD(d0);
      d0 = SREG[PREG->u.sllll.s];
      deref_head(d0, sub_arg_swt_unk);
      /* nonvar */
    sub_arg_swt_nvar:
      if (IsPairTerm(d0)) {
      /* pair */
      copy_jmp_address(PREG->u.sllll.l1);
      PREG = PREG->u.sllll.l1;
      SREG = RepPair(d0);
      JMPNext();
      }
      else if (!IsApplTerm(d0)) {
      /* constant */
      copy_jmp_address(PREG->u.sllll.l2);
      PREG = PREG->u.sllll.l2;
      I_R = d0;
      JMPNext();
      }
      else {
      /* appl */
      copy_jmp_address(PREG->u.sllll.l3);
      PREG = PREG->u.sllll.l3;
      SREG = RepAppl(d0);
      JMPNext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, sub_arg_swt_unk, sub_arg_swt_nvar);
      /* variable */
      copy_jmp_address(PREG->u.sllll.l4);
      PREG = PREG->u.sllll.l4;
      JMPNext();
      ENDP(pt0);
      ENDD(d0);
      ENDBOp();

      BOp(jump_if_var, l);
      BEGD(d0);
      d0 = CACHED_A1();
      deref_head(d0, jump_if_unk);
      /* non var */
    jump0_if_nonvar:
      PREG = NEXTOP(PREG, l);
      JMPNext();

      BEGP(pt0);
      deref_body(d0, pt0, jump_if_unk, jump0_if_nonvar);
      /* variable */
      copy_jmp_address(PREG->u.l.l);
      PREG = PREG->u.l.l;
      ENDP(pt0);
      JMPNext();
      ENDD(d0);
      ENDBOp();

      BOp(jump_if_nonvar, xll);
      BEGD(d0);
      d0 = XREG(PREG->u.xll.x);
      deref_head(d0, jump2_if_unk);
      /* non var */
    jump2_if_nonvar:
      copy_jmp_address(PREG->u.xll.l1);
      PREG = PREG->u.xll.l1;
      JMPNext();

      BEGP(pt0);
      deref_body(d0, pt0, jump2_if_unk, jump2_if_nonvar);
      /* variable */
      PREG = NEXTOP(PREG, xll);
      ENDP(pt0);
      JMPNext();
      ENDD(d0);
      ENDBOp();

      BOp(if_not_then, clll);
      BEGD(d0);
      d0 = CACHED_A1();
      deref_head(d0, if_n_unk);
    if_n_nvar:
      /* not variable */
      if (d0 == PREG->u.clll.c) {
      /* equal to test value */
      copy_jmp_address(PREG->u.clll.l2);
      PREG = PREG->u.clll.l2;
      JMPNext();
      }
      else {
      /* different from test value */
      /* the case to optimise */
      copy_jmp_address(PREG->u.clll.l1);
      PREG = PREG->u.clll.l1;
      JMPNext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, if_n_unk, if_n_nvar);
      ENDP(pt0);
      /* variable */
      copy_jmp_address(PREG->u.clll.l3);
      PREG = PREG->u.clll.l3;
      JMPNext();
      ENDD(d0);
      ENDBOp();

/************************************************************************\
*     Indexing on ARG1                                      *
\************************************************************************/

#define HASH_SHIFT 6

      BOp(switch_on_func, sssl);
      BEGD(d1);
      d1 = *SREG++;
      /* we use a very simple hash function to find elements in a
       * switch table */
      {
      CELL
      /* first, calculate the mask */
        Mask = (PREG->u.sssl.s - 1) << 1, /* next, calculate the hash function */
        hash = d1 >> (HASH_SHIFT - 1) & Mask;
      CELL *base;

      base = (CELL *)PREG->u.sssl.l;
      /* PREG now points at the beginning of the hash table */
      BEGP(pt0);
      /* pt0 will always point at the item */
      pt0 = base + hash;
      BEGD(d0);
      d0 = pt0[0];
      /* a match happens either if we found the value, or if we
       * found an empty slot */
      if (d0 == d1 || d0 == 0) {
        copy_jmp_addressa(pt0+1);
        PREG = (yamop *) (pt0[1]);
        JMPNext();
      }
      else {
        /* ooops, collision, look for other items   */
        register CELL d = ((d1 | 1) << 1) & Mask;

        while (1) {
          hash = (hash + d) & Mask;
          pt0 = base + hash;
          d0 = pt0[0];
          if (d0 == d1 || d0 == 0) {
            copy_jmp_addressa(pt0+1);
            PREG = (yamop *) pt0[1];
            JMPNext();
          }
        }
      }
      ENDD(d0);
      ENDP(pt0);
      }
      ENDD(d1);
      ENDBOp();

      BOp(switch_on_cons, sssl);
      BEGD(d1);
      d1 = I_R;
      /* we use a very simple hash function to find elements in a
       * switch table */
      {
      CELL
      /* first, calculate the mask */
        Mask = (PREG->u.sssl.s - 1) << 1, /* next, calculate the hash function */
        hash = d1 >> (HASH_SHIFT - 1) & Mask;
      CELL *base;

      base = (CELL *)PREG->u.sssl.l;
      /* PREG now points at the beginning of the hash table */
      BEGP(pt0);
      /* pt0 will always point at the item */
      pt0 = base + hash;
      BEGD(d0);
      d0 = pt0[0];
      /* a match happens either if we found the value, or if we
       * found an empty slot */
      if (d0 == d1 || d0 == 0) {
        copy_jmp_addressa(pt0+1);
        PREG = (yamop *) (pt0[1]);
        JMPNext();
      }
      else {
        /* ooops, collision, look for other items   */
        register CELL d = ((d1 | 1) << 1) & Mask;

        while (1) {
          hash = (hash + d) & Mask;
          pt0 = base + hash;
          d0 = pt0[0];
          if (d0 == d1 || d0 == 0) {
            copy_jmp_addressa(pt0+1);
            PREG = (yamop *) pt0[1];
            JMPNext();
          }
        }
      }
      ENDD(d0);
      ENDP(pt0);
      }
      ENDD(d1);
      ENDBOp();

      BOp(go_on_func, sssl);
      BEGD(d0);
      {
      CELL *pt = (CELL *)(PREG->u.sssl.l);

      d0 = *SREG++;
      if (d0 == pt[0]) {
        copy_jmp_addressa(pt+1);
        PREG = (yamop *) pt[1];
        JMPNext();
      } else {
        copy_jmp_addressa(pt+3);
        PREG = (yamop *) pt[3];
        JMPNext();
      }
      }
      ENDD(d0);
      ENDBOp();

      BOp(go_on_cons, sssl);
      BEGD(d0);
      {
      CELL *pt = (CELL *)(PREG->u.sssl.l);

      d0 = I_R;
      if (d0 == pt[0]) {
        copy_jmp_addressa(pt+1);
        PREG = (yamop *) pt[1];
        JMPNext();
      } else {
        copy_jmp_addressa(pt+3);
        PREG = (yamop *) pt[3];
        JMPNext();
      }
      }
      ENDD(d0);
      ENDBOp();

      BOp(if_func, sssl);
      BEGD(d1);
      BEGP(pt0);
      pt0 = (CELL *) PREG->u.sssl.l;
      d1 = *SREG++;
      while (pt0[0] != d1 && pt0[0] != (CELL)NULL ) {
      pt0 += 2;
      }
      copy_jmp_addressa(pt0+1);
      PREG = (yamop *) (pt0[1]);
      JMPNext();
      ENDP(pt0);
      ENDD(d1);
      ENDBOp();

      BOp(if_cons, sssl);
      BEGD(d1);
      BEGP(pt0);
      pt0 = (CELL *) PREG->u.sssl.l;
      d1 = I_R;
      while (pt0[0] != d1 && pt0[0] != 0L ) {
      pt0 += 2;
      }
      copy_jmp_addressa(pt0+1);
      PREG = (yamop *) (pt0[1]);
      JMPNext();
      ENDP(pt0);
      ENDD(d1);
      ENDBOp();

      Op(index_dbref, e);
      PREG = NEXTOP(PREG, e);
      I_R = AbsAppl(SREG-1);
      GONext();
      ENDOp();
      
      Op(index_blob, e);
      PREG = NEXTOP(PREG, e);
      I_R = MkIntTerm(SREG[0]);
      GONext();
      ENDOp();
      


/************************************************************************\
*     Basic Primitive Predicates                             *
\************************************************************************/

      Op(p_atom_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, atom_x_unk);
    atom_x_nvar:
      if (IsAtomTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      else {
      PREG = PREG->u.xF.F;
      GONext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, atom_x_unk, atom_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_atom_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, atom_y_unk);
    atom_y_nvar:
      if (IsAtomTerm(d0)) {
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      else {
      PREG = PREG->u.yF.F;
      GONext();
      }

      derefa_body(d0, pt0, atom_y_unk, atom_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_atomic_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, atomic_x_unk);
    atomic_x_nvar:
      /* non variable */
      if (IsAtomicTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      else {
      PREG = PREG->u.xF.F;
      GONext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, atomic_x_unk, atomic_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_atomic_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, atomic_y_unk);
    atomic_y_nvar:
      /* non variable */
      if (IsAtomicTerm(d0)) {
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      else {
      PREG = PREG->u.yF.F;
      GONext();
      }

      derefa_body(d0, pt0, atomic_y_unk, atomic_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_integer_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, integer_x_unk);
    integer_x_nvar:
      /* non variable */
      if (IsIntTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      if (IsApplTerm(d0)) {
      Functor f0 = FunctorOfTerm(d0);
      if (IsExtensionFunctor(f0)) {
        switch ((CELL)f0) {
        case (CELL)FunctorLongInt:
#ifdef USE_GMP
        case (CELL)FunctorBigInt:
#endif
          PREG = NEXTOP(PREG, xF);
          GONext();
        default:
          PREG = PREG->u.xF.F;
          GONext();
        }
      }
      }
      PREG = PREG->u.xF.F;
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, integer_x_unk, integer_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_integer_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, integer_y_unk);
    integer_y_nvar:
      /* non variable */
      if (IsIntTerm(d0)) {
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      if (IsApplTerm(d0)) {
      Functor f0 = FunctorOfTerm(d0);
      if (IsExtensionFunctor(f0)) {
        switch ((CELL)f0) {
        case (CELL)FunctorLongInt:
#ifdef USE_GMP
        case (CELL)FunctorBigInt:
#endif
          PREG = NEXTOP(PREG, yF);
          GONext();
        default:
          PREG = PREG->u.yF.F;
          GONext();
        }
      }
      }
      PREG = PREG->u.yF.F;
      GONext();

      derefa_body(d0, pt0, integer_y_unk, integer_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_nonvar_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, nonvar_x_unk);
    nonvar_x_nvar:
      PREG = NEXTOP(PREG, xF);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, nonvar_x_unk, nonvar_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_nonvar_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, nonvar_y_unk);
    nonvar_y_nvar:
      PREG = NEXTOP(PREG, yF);
      GONext();

      derefa_body(d0, pt0, nonvar_y_unk, nonvar_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_number_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, number_x_unk);
    number_x_nvar:
      /* non variable */
      if (IsIntTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      if (IsApplTerm(d0)) {
      Functor f0 = FunctorOfTerm(d0);
      if (IsExtensionFunctor(f0)) {
        switch ((CELL)f0) {
        case (CELL)FunctorLongInt:
        case (CELL)FunctorDouble:
#ifdef USE_GMP
        case (CELL)FunctorBigInt:
#endif
          PREG = NEXTOP(PREG, xF);
          GONext();
        default:
          PREG = PREG->u.xF.F;
          GONext();
        } 
      } 
      }
      PREG = PREG->u.xF.F;
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, number_x_unk, number_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_number_y, xF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, number_y_unk);
    number_y_nvar:
      /* non variable */
      /* non variable */
      if (IsIntTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      if (IsApplTerm(d0)) {
      Functor f0 = FunctorOfTerm(d0);
      if (IsExtensionFunctor(f0)) {
        switch ((CELL)f0) {
        case (CELL)FunctorLongInt:
        case (CELL)FunctorDouble:
#ifdef USE_GMP
        case (CELL)FunctorBigInt:
#endif
          PREG = NEXTOP(PREG, yF);
          GONext();
        default:
          PREG = PREG->u.yF.F;
          GONext();
        } 
      }
      }
      PREG = PREG->u.xF.F;
      GONext();

      derefa_body(d0, pt0, number_y_unk, number_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_var_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, var_x_unk);
    var_x_nvar:
      /* non variable */
      PREG = PREG->u.xF.F;
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, var_x_unk, var_x_nvar);
      PREG = NEXTOP(PREG, xF);
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_var_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, var_y_unk);
    var_y_nvar:
      /* non variable */
      PREG = PREG->u.yF.F;
      GONext();

      derefa_body(d0, pt0, var_y_unk, var_y_nvar);
      PREG = NEXTOP(PREG, yF);
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_db_ref_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, dbref_x_unk);
    dbref_x_nvar:
      /* non variable */
      if (IsDBRefTerm(d0)) {
      /* only allow references to the database, not general references
       * to go through. */
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      else {
      PREG = PREG->u.xF.F;
      GONext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, dbref_x_unk, dbref_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_db_ref_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, dbref_y_unk);
    dbref_y_nvar:
      /* non variable */
      if (IsDBRefTerm(d0)) {
      /* only allow references to the database, not general references
       * to go through. */
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      else {
      PREG = PREG->u.yF.F;
      GONext();
      }

      derefa_body(d0, pt0, dbref_y_unk, dbref_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_primitive_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, primi_x_unk);
    primi_x_nvar:
      /* non variable */
      if (IsPrimitiveTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      else {
      PREG = PREG->u.xF.F;
      GONext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, primi_x_unk, primi_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_primitive_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, primi_y_unk);
    primi_y_nvar:
      /* non variable */
      if (IsPrimitiveTerm(d0)) {
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      else {
      PREG = PREG->u.yF.F;
      GONext();
      }

      derefa_body(d0, pt0, primi_y_unk, primi_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_compound_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, compound_x_unk);
    compound_x_nvar:
      /* non variable */
      if (IsPairTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      else if (IsApplTerm(d0)) {
      if (IsExtensionFunctor(FunctorOfTerm(d0))) {
        PREG = PREG->u.xF.F;
        GONext();
      }
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      else {
      PREG = PREG->u.xF.F;
      GONext();
      }

      BEGP(pt0);
      deref_body(d0, pt0, compound_x_unk, compound_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_compound_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, compound_y_unk);
    compound_y_nvar:
      /* non variable */
      if (IsPairTerm(d0)) {
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      else if (IsApplTerm(d0)) {
      if (IsExtensionFunctor(FunctorOfTerm(d0))) {
        PREG = PREG->u.yF.F;
        GONext();
      }
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      else {
      PREG = PREG->u.yF.F;
      GONext();
      }

      derefa_body(d0, pt0, compound_y_unk, compound_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_float_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, float_x_unk);
    float_x_nvar:
      /* non variable */
      if (IsFloatTerm(d0)) {
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      PREG = PREG->u.xF.F;
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, float_x_unk, float_x_nvar);
      PREG = PREG->u.xF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_float_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, float_y_unk);
    float_y_nvar:
      /* non variable */
      if (IsFloatTerm(d0)) {
      PREG = NEXTOP(PREG, yF);
      GONext();
      }
      PREG = PREG->u.yF.F;
      GONext();

      derefa_body(d0, pt0, float_y_unk, float_y_nvar);
      PREG = PREG->u.yF.F;
      GONext();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_cut_by_x, xF);
      BEGD(d0);
      d0 = XREG(PREG->u.xF.x);
      deref_head(d0, cutby_x_unk);
    cutby_x_nvar:
#if defined(SBA) && defined(FROZEN_STACKS)
      if (!IsIntegerTerm(d0)) {
#else
      if (!IsIntTerm(d0)) {
#endif /* SBA && FROZEN_STACKS */
      PREG = NEXTOP(PREG, xF);
      GONext();
      }
      BEGCHO(pt0);
#if defined(SBA) && defined(FROZEN_STACKS)
      pt0 = (choiceptr)IntegerOfTerm(d0);
#else
      pt0 = (choiceptr)(LCL0-IntOfTerm(d0));
#endif /* SBA && FROZEN_STACKS */
#ifdef CUT_C
      {
      if (SHOULD_CUT_UP_TO(B, pt0))
        {
          while (POP_CHOICE_POINT(pt0))
            {
            POP_EXECUTE();
            }
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to(pt0);
#endif /* YAPOR */
      /* find where to cut to */
      if (SHOULD_CUT_UP_TO(B,pt0)) {
      /* Wow, we're gonna cut!!! */
      while (B->cp_b < pt0) {
        B = B->cp_b;
      }
#ifdef TABLING
      abolish_incomplete_subgoals(B);
#endif /* TABLING */
      goto trim_trail;
      }
      PREG = NEXTOP(PREG, xF);
      ENDCHO(pt0);
      GONext();

      BEGP(pt1);
      deref_body(d0, pt1, cutby_x_unk, cutby_x_nvar);
      ENDP(pt1);
      /* never cut to a variable */
      /* Abort */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_cut_by_y, yF);
      BEGD(d0);
      BEGP(pt0);
      pt0 = YREG + PREG->u.yF.y;
      d0 = *pt0;
      deref_head(d0, cutby_y_unk);
    cutby_y_nvar:
#if defined(SBA) && defined(FROZEN_STACKS)
      if (!IsIntegerTerm(d0)) {
#else
      if (!IsIntTerm(d0)) {
#endif
      FAIL();
      }
      /* find where to cut to */
      BEGCHO(pt1);
#if defined(SBA) && defined(FROZEN_STACKS)
      pt1 = (choiceptr)IntegerOfTerm(d0);
#else
      pt1 = (choiceptr)(LCL0-IntOfTerm(d0));
#endif /* SBA && FROZEN_STACKS */
#ifdef CUT_C
      {
      if (SHOULD_CUT_UP_TO(B,(choiceptr) pt1))
        {
          while (POP_CHOICE_POINT(pt1))
            {
            POP_EXECUTE();
            }
        }
      }
#endif /* CUT_C */
#ifdef YAPOR
      CUT_prune_to(pt1);
#endif /* YAPOR */
      if (SHOULD_CUT_UP_TO(B,pt1)) {
      /* Wow, we're gonna cut!!! */
      while (B->cp_b < pt1) {
        B = B->cp_b;
      }
#ifdef TABLING
      abolish_incomplete_subgoals(B);
#endif /* TABLING */
      goto trim_trail;
      }
      PREG = NEXTOP(PREG, yF);
      GONext();
      ENDCHO(pt1);

      derefa_body(d0, pt0, cutby_y_unk, cutby_y_nvar);
      /* never cut to a variable */
      /* Abort */
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_plus_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, plus_vv_unk);
    plus_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, plus_vv_nvar_unk);
    plus_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) + IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_plus(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, plus_vv_unk, plus_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is _+B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, plus_vv_nvar_unk, plus_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A+B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_plus_vc, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, plus_vc_unk);
    plus_vc_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(IntOfTerm(d0) + d1);
      }
      else {
        saveregs();
        d0 = p_plus(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, plus_vc_unk, plus_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A+B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_plus_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, plus_y_vv_unk);
    plus_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, plus_y_vv_nvar_unk);
    plus_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) + IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_plus(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, plus_y_vv_unk, plus_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A+B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, plus_y_vv_nvar_unk, plus_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A+B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_plus_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      /* first check pt1 */
      deref_head(d0, plus_y_vc_unk);
    plus_y_vc_nvar:
      {
      Int d1 = PREG->u.yxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(IntOfTerm(d0) + d1);
      }
      else {
        saveregs();
        d0 = p_plus(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, plus_y_vc_unk, plus_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A+B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_minus_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, minus_vv_unk);
    minus_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, minus_vv_nvar_unk);
    minus_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) - IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_minus(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, minus_vv_unk, minus_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A-B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, minus_vv_nvar_unk, minus_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A-B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_minus_cv, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, minus_cv_unk);
    minus_cv_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(d1 - IntOfTerm(d0));
      }
      else {
        saveregs();
        d0 = p_minus(MkIntegerTerm(d1),d0);
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, minus_cv_unk, minus_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A-B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_minus_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, minus_y_vv_unk);
    minus_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, minus_y_vv_nvar_unk);
    minus_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) - IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_minus(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, minus_y_vv_unk, minus_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A-B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, minus_y_vv_nvar_unk, minus_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A-B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_minus_y_cv, ycx);
      BEGD(d0);
      d0 = XREG(PREG->u.ycx.xi);
      /* first check pt1 */
      deref_head(d0, minus_y_cv_unk);
    minus_y_cv_nvar:
      {
      Int d1 = PREG->u.ycx.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(d1 - IntOfTerm(d0));
      }
      else {
        saveregs();
        d0 = p_minus(MkIntegerTerm(d1), d0);
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(PREG, ycx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, minus_y_cv_unk, minus_y_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A-B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_times_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, times_vv_unk);
    times_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, times_vv_nvar_unk);
    times_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = times_int(IntOfTerm(d0), IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_times(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, times_vv_unk, times_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A*B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, times_vv_nvar_unk, times_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A*B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_times_vc, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, times_vc_unk);
    times_vc_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = times_int(IntOfTerm(d0), d1);
      }
      else {
        saveregs();
        d0 = p_times(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, times_vc_unk, times_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A*B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_times_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, times_y_vv_unk);
    times_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, times_y_vv_nvar_unk);
    times_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = times_int(IntOfTerm(d0), IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_times(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, times_y_vv_unk, times_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A*B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, times_y_vv_nvar_unk, times_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A*B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_times_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      /* first check pt1 */
      deref_head(d0, times_y_vc_unk);
    times_y_vc_nvar:
      {
      Int d1 = PREG->u.yxc.c;
      if (IsIntTerm(d0)) {
        d0 = times_int(IntOfTerm(d0), d1);
      }
      else {
        saveregs();
        d0 = p_times(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, times_y_vc_unk, times_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A*B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_div_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, div_vv_unk);
    div_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, div_vv_nvar_unk);
    div_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      Int div = IntOfTerm(d1);
      if (div == 0) {
        saveregs();
        Yap_Error(EVALUATION_ERROR_ZERO_DIVISOR,TermNil,"// /2");
        setregs();
        FAIL();
      }
      d0 = MkIntTerm(IntOfTerm(d0) / div);
      }
      else {
      saveregs();
      d0 = p_div(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, div_vv_unk, div_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, div_vv_nvar_unk, div_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_div_vc, xcx);
      BEGD(d0);
      d0 = XREG(PREG->u.xcx.xi);
      /* first check pt1 */
      deref_head(d0, div_vc_unk);
    div_vc_nvar:
      {
      Int d1 = PREG->u.xcx.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntTerm(IntOfTerm(d0) / d1);
      }
      else {
        saveregs();
        d0 = p_div(d0,MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xcx.x) = d0;
      PREG = NEXTOP(PREG, xcx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, div_vc_unk, div_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_div_cv, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, div_cv_unk);
    div_cv_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        Int div = IntOfTerm(d0);
        if (div == 0){
          saveregs();
          Yap_Error(EVALUATION_ERROR_ZERO_DIVISOR,TermNil,"// /2");
          setregs();
          FAIL();
        }
        d0 = MkIntegerTerm(d1 / div);
      }
      else {
        saveregs();
        d0 = p_div(MkIntegerTerm(d1),d0);
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, div_cv_unk, div_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_div_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, div_y_vv_unk);
    div_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, div_y_vv_nvar_unk);
    div_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      Int div = IntOfTerm(d1);
      if (div == 0) {
        saveregs();
        Yap_Error(EVALUATION_ERROR_ZERO_DIVISOR,TermNil,"// /2");
        setregs();
        FAIL();
      }
      d0 = MkIntTerm(IntOfTerm(d0) / div);
      }
      else {
      saveregs();
      d0 = p_div(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, div_y_vv_unk, div_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, div_y_vv_nvar_unk, div_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_div_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.ycx.xi);
      /* first check pt1 */
      deref_head(d0, div_y_vc_unk);
    div_y_vc_nvar:
      {
      Int d1 = PREG->u.ycx.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntTerm(IntOfTerm(d0)/d1);
      }
      else {
        saveregs();
        d0 = p_div(d0,MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, div_y_vc_unk, div_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_div_y_cv, ycx);
      BEGD(d0);
      d0 = XREG(PREG->u.ycx.xi);
      /* first check pt1 */
      deref_head(d0, div_y_cv_unk);
    div_y_cv_nvar:
      {
      Int d1 = PREG->u.ycx.c;
      if (IsIntTerm(d0)) {
        Int div = IntOfTerm(d0);
        if (div == 0) {
          saveregs();
          Yap_Error(EVALUATION_ERROR_ZERO_DIVISOR,TermNil,"// /2");
          setregs();
          FAIL();
        }
        d0 = MkIntegerTerm(d1 / div);
      }
      else {
        saveregs();
        d0 = p_div(MkIntegerTerm(d1), d0);
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(PREG, ycx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, div_y_cv_unk, div_y_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A//B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();


      Op(p_and_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, and_vv_unk);
    and_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, and_vv_nvar_unk);
    and_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) & IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_and(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, and_vv_unk, and_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A/\\B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, and_vv_nvar_unk, and_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A/\\B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_and_vc, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, and_vc_unk);
    and_vc_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(IntOfTerm(d0) & d1);
      }
      else {
        saveregs();
        d0 = p_and(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, and_vc_unk, and_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A/\\B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_and_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, and_y_vv_unk);
    and_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, and_y_vv_nvar_unk);
    and_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) & IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_and(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, and_y_vv_unk, and_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A/\\B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, and_y_vv_nvar_unk, and_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A/\\B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_and_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      /* first check pt1 */
      deref_head(d0, and_y_vc_unk);
    and_y_vc_nvar:
      {
      Int d1 = PREG->u.yxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(IntOfTerm(d0) & d1);
      }
      else {
        saveregs();
        d0 = p_and(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, and_y_vc_unk, and_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A/\\B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();


      Op(p_or_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, or_vv_unk);
    or_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, or_vv_nvar_unk);
    or_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) | IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_or(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, or_vv_unk, or_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A\\/B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, or_vv_nvar_unk, or_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A\\/B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_or_vc, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, or_vc_unk);
    or_vc_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(IntOfTerm(d0) | d1);
      }
      else {
        saveregs();
        d0 = p_or(d0, MkIntegerTerm(d1));
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, or_vc_unk, or_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A\\/B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_or_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, or_y_vv_unk);
    or_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, or_y_vv_nvar_unk);
    or_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      d0 = MkIntegerTerm(IntOfTerm(d0) | IntOfTerm(d1));
      }
      else {
      saveregs();
      d0 = p_or(d0, d1);
      setregs();
      if (PREG == (yamop *)FAILCODE)
        FAIL();
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, or_y_vv_unk, or_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A\\/B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, or_y_vv_nvar_unk, or_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A\\/B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_or_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      /* first check pt1 */
      deref_head(d0, or_y_vc_unk);
    or_y_vc_nvar:
      {
      Int d1 = PREG->u.yxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntegerTerm(IntOfTerm(d0) | d1);
      }
      else {
        saveregs();
        d0 = p_or(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, or_y_vc_unk, or_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A\\/B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_sll_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, sll_vv_unk);
    sll_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, sll_vv_nvar_unk);
    sll_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      Int i2 = IntOfTerm(d1);
      if (i2 < 0)
        d0 = MkIntegerTerm(IntOfTerm(d0) >> -i2);
      else
        d0 = do_sll(IntOfTerm(d0),i2);
      }
      else {
      saveregs();
      d0 = p_sll(d0, d1);
      setregs();
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, sll_vv_unk, sll_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, sll_vv_nvar_unk, sll_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_sll_vc, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, sll_vc_unk);
    sll_vc_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = do_sll(IntOfTerm(d0), (Int)d1);
      }
      else {
        saveregs();
        d0 = p_sll(d0, MkIntegerTerm(d1));
        setregs();
      }
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, sll_vc_unk, sll_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_sll_cv, xcx);
      BEGD(d0);
      d0 = XREG(PREG->u.xcx.xi);
      /* first check pt1 */
      deref_head(d0, sll_cv_unk);
    sll_cv_nvar:
      {
      Int d1 = PREG->u.xcx.c;
      if (IsIntTerm(d0)) {
        Int i2 = IntOfTerm(d0);
        if (i2 < 0)
          d0 = MkIntegerTerm(d1 >> -i2);
        else
          d0 = do_sll(d1,i2);
      }
      else {
        saveregs();
        d0 = p_sll(MkIntegerTerm(d1), d0);
        setregs();
      }
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xcx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, sll_cv_unk, sll_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_sll_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, sll_y_vv_unk);
    sll_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, sll_y_vv_nvar_unk);
    sll_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      Int i2 = IntOfTerm(d1);
      if (i2 < 0)
        d0 = MkIntegerTerm(IntOfTerm(d0) >> -i2);
      else
        d0 = do_sll(IntOfTerm(d0),i2);
      }
      else {
      saveregs();
      d0 = p_sll(d0, d1);
      setregs();
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, sll_y_vv_unk, sll_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, sll_y_vv_nvar_unk, sll_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_sll_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      /* first check pt1 */
      deref_head(d0, sll_y_vc_unk);
    sll_y_vc_nvar:
      {
      Int d1 = PREG->u.yxc.c;
      if (IsIntTerm(d0)) {
        d0 = do_sll(IntOfTerm(d0), d1);
      }
      else {
        saveregs();
        d0 = p_sll(d0, MkIntegerTerm(d1));
        setregs();
      }
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, sll_y_vc_unk, sll_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();


      Op(p_sll_y_cv, ycx);
      BEGD(d0);
      d0 = XREG(PREG->u.ycx.xi);
      /* first check pt1 */
      deref_head(d0, sll_y_cv_unk);
    sll_y_cv_nvar:
      {
      Int d1 = PREG->u.ycx.c;
      if (IsIntTerm(d0)) {
        Int i2 = IntOfTerm(d0);
        if (i2 < 0)
          d0 = MkIntegerTerm(d1 >> -i2);
        else
          d0 = do_sll(d1,i2);
      }
      else {
        saveregs();
        d0 = p_sll(MkIntegerTerm(d1), d0);
        setregs();
      }
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      BEGP(pt0);
      pt0 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(PREG, ycx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, sll_y_cv_unk, sll_y_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A<<B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_slr_vv, xxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.xxx.x1);
      /* first check pt1 */
      deref_head(d0, slr_vv_unk);
    slr_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, slr_vv_nvar_unk);
    slr_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      Int i2 = IntOfTerm(d1);
      if (i2 < 0)
        d0 = do_sll(IntOfTerm(d0), -i2);
      else
        d0 = MkIntTerm(IntOfTerm(d0) >> i2);
      }
      else {
      saveregs();
      d0 = p_slr(d0, d1);
      setregs();
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(PREG, xxx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, slr_vv_unk, slr_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, slr_vv_nvar_unk, slr_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_slr_vc, xxc);
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      /* first check pt1 */
      deref_head(d0, slr_vc_unk);
    slr_vc_nvar:
      {
      Int d1 = PREG->u.xxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntTerm(IntOfTerm(d0) >> d1);
      }
      else {
        saveregs();
        d0 = p_slr(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xxc);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, slr_vc_unk, slr_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_slr_cv, xcx);
      BEGD(d0);
      d0 = XREG(PREG->u.xcx.xi);
      /* first check pt1 */
      deref_head(d0, slr_cv_unk);
    slr_cv_nvar:
      {
      Int d1 = PREG->u.xcx.c;
      if (IsIntTerm(d0)) {
       Int i2 = IntOfTerm(d0);
       if (i2 < 0)
         d0 = do_sll(d1, -i2);
       else
         d0 = MkIntTerm(d1 >> i2);
      }
      else {
        saveregs();
        d0 = p_slr(MkIntegerTerm(d1), d0);
        setregs();
      }
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(PREG, xcx);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, slr_cv_unk, slr_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_slr_y_vv, yxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.yxx.x1);
      /* first check pt1 */
      deref_head(d0, slr_y_vv_unk);
    slr_y_vv_nvar:
      d1 = XREG(PREG->u.xxx.x2);
      /* next check A2 */
      deref_head(d1, slr_y_vv_nvar_unk);
    slr_y_vv_nvar_nvar:
      /* d0 and d1 are where I want them */
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
       Int i2 = IntOfTerm(d1);
       if (i2 < 0)
         d0 = do_sll(IntOfTerm(d0), -i2);
       else
         d0 = MkIntTerm(IntOfTerm(d0) >> i2);
      }
      else {
      saveregs();
      d0 = p_slr(d0, d1);
      setregs();
      }
      BEGP(pt0);
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      pt0 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, slr_y_vv_unk, slr_y_vv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, slr_y_vv_nvar_unk, slr_y_vv_nvar_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_slr_y_vc, yxc);
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      /* first check pt1 */
      deref_head(d0, slr_y_vc_unk);
    slr_y_vc_nvar:
      {
      Int d1 = PREG->u.yxc.c;
      if (IsIntTerm(d0)) {
        d0 = MkIntTerm(IntOfTerm(d0) >> d1);
      }
      else {
        saveregs();
        d0 = p_slr(d0, MkIntegerTerm(d1));
        setregs();
        if (PREG == (yamop *)FAILCODE)
          FAIL();
      }
      }
      BEGP(pt0);
      pt0 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, slr_y_vc_unk, slr_y_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      Op(p_slr_y_cv, ycx);
      BEGD(d0);
      d0 = XREG(PREG->u.ycx.xi);
      /* first check pt1 */
      deref_head(d0, slr_y_cv_unk);
    slr_y_cv_nvar:
      {
      Int d1 = PREG->u.ycx.c;
      if (IsIntTerm(d0)) {
       Int i2 = IntOfTerm(d0);
       if (i2 < 0)
         d0 = do_sll(d1, -i2);
       else
         d0 = MkIntTerm(d1 >> i2);
      }
      else {
        saveregs();
        d0 = p_slr(MkIntegerTerm(d1), d0);
        setregs();
      }
      }
      if (PREG == (yamop *)FAILCODE)
      FAIL();
      BEGP(pt0);
      pt0 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(PREG, ycx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt0,d0);
#else
      *pt0 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt0);
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, slr_y_cv_unk, slr_y_cv_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, TermNil, "X is A>>B");
      setregs();
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      BOp(call_bfunc_xx, llxx);
      BEGD(d0);
      BEGD(d1);
      d0 = XREG(PREG->u.llxx.x1);
    call_bfunc_xx_nvar:
      d1 = XREG(PREG->u.llxx.x2);
    call_bfunc_xx2_nvar:
      deref_head(d0, call_bfunc_xx_unk);
      deref_head(d1, call_bfunc_xx2_unk);
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      int flags;

      Int v = IntOfTerm(d0) - IntOfTerm(d1);
      flags = PREG->u.llxx.flags;
      if (v > 0) {
        if (flags & GT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxx);
          JMPNext();
        } else {
          PREG = PREG->u.llxx.f;
          JMPNext();
        }    
      } else if (v < 0) {
        if (flags & LT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxx);
          JMPNext();
        } else {
          PREG = PREG->u.llxx.f;
          JMPNext();
        }
      } else /* if (v == 0) */ {
        if (flags & EQ_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxx);
          JMPNext();
        } else {
          PREG = PREG->u.llxx.f;
          JMPNext();
        }
      }
      } 
    exec_bin_cmp_xx:
      {
       CmpPredicate f = PREG->u.llxx.p->cs.d_code;
       saveregs();
       d0 = (CELL) (f) (d0,d1);
       setregs();
      }
      if (!d0) {
      if (PREG != FAILCODE)
        PREG = PREG->u.llxx.f;
      JMPNext();
      }
      PREG = NEXTOP(PREG, llxx);
      JMPNext();

      BEGP(pt0);
      deref_body(d0, pt0, call_bfunc_xx_unk, call_bfunc_xx_nvar);
      d1 = Deref(d1);
      goto exec_bin_cmp_xx;
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, call_bfunc_xx2_unk, call_bfunc_xx2_nvar);
      goto exec_bin_cmp_xx;
      ENDP(pt0);

      ENDD(d1);
      ENDD(d0);
      ENDBOp();

      BOp(call_bfunc_yx, llxy);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = YREG + PREG->u.llxy.y;
      d1 = XREG(PREG->u.llxy.x);
      d0 = *pt0;
      ENDP(pt0);
      deref_head(d0, call_bfunc_yx_unk);
    call_bfunc_yx_nvar:
      deref_head(d1, call_bfunc_yx2_unk);
    call_bfunc_yx2_nvar:
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      int flags;

      Int v = IntOfTerm(d0) - IntOfTerm(d1);
      flags = PREG->u.llxy.flags;
      if (v > 0) {
        if (flags & GT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxy);
          JMPNext();
        } else {
          PREG = PREG->u.llxy.f;
          JMPNext();
        }
      } else if (v < 0) {
        if (flags & LT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxy);
          JMPNext();
        } else {
          PREG = PREG->u.llxy.f;
          JMPNext();
        }
      } else /* if (v == 0) */ {
        if (flags & EQ_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxy);
          JMPNext();
        } else {
          PREG = PREG->u.llxy.f;
          JMPNext();
        }
      }
      } 
    exec_bin_cmp_yx:
      {
      CmpPredicate f = PREG->u.llxy.p->cs.d_code;
      saveregs();
      d0 = (CELL) (f) (d0,d1);
      setregs();
      }
      if (!d0) {
      if (PREG != FAILCODE)
        PREG = PREG->u.llxy.f;
      JMPNext();
      }
      PREG = NEXTOP(PREG, llxy);
      JMPNext();

      BEGP(pt0);
      deref_body(d0, pt0, call_bfunc_yx_unk, call_bfunc_yx_nvar);
      d1 = Deref(d1);
      goto exec_bin_cmp_yx;
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, call_bfunc_yx2_unk, call_bfunc_yx2_nvar);
      goto exec_bin_cmp_yx;
      ENDP(pt0);

      ENDD(d1);
      ENDD(d0);
      ENDBOp();

      BOp(call_bfunc_xy, llxy);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = YREG + PREG->u.llxy.y;
      d0 = XREG(PREG->u.llxy.x);
      d1 = *pt0;
      ENDP(pt0);
      deref_head(d0, call_bfunc_xy_unk);
    call_bfunc_xy_nvar:
      deref_head(d1, call_bfunc_xy2_unk);
    call_bfunc_xy2_nvar:
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      int flags;

      Int v = IntOfTerm(d0) - IntOfTerm(d1);
      flags = PREG->u.llxy.flags;
      if (v > 0) {
        if (flags & GT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxy);
          JMPNext();
        } else {
          PREG = PREG->u.llxy.f;
          JMPNext();
        }
      } else if (v < 0) {
        if (flags & LT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxy);
          JMPNext();
        } else {
          PREG = PREG->u.llxy.f;
          JMPNext();
        }
      } else /* if (v == 0) */ {
        if (flags & EQ_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llxy);
          JMPNext();
        } else {
          PREG = PREG->u.llxy.f;
          JMPNext();
        }
      }
      } 
    exec_bin_cmp_xy:
      {
      CmpPredicate f = PREG->u.llxy.p->cs.d_code;
      saveregs();
      d0 = (CELL) (f) (d0,d1);
      setregs();
      }
      if (!d0) {
      if (PREG != FAILCODE)
        PREG = PREG->u.llxy.f;
      JMPNext();
      }
      PREG = NEXTOP(PREG, llxy);
      JMPNext();

      BEGP(pt0);
      deref_body(d0, pt0, call_bfunc_xy_unk, call_bfunc_xy_nvar);
      d1 = Deref(d1);
      goto exec_bin_cmp_xy;
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, call_bfunc_xy2_unk, call_bfunc_xy2_nvar);
      goto exec_bin_cmp_xy;
      ENDP(pt0);

      ENDD(d1);
      ENDD(d0);
      ENDBOp();

      BOp(call_bfunc_yy, llyy);
      BEGD(d0);
      BEGD(d1);
      BEGP(pt0);
      pt0 = YREG + PREG->u.llyy.y1;
      BEGP(pt1);
      pt1 = YREG + PREG->u.llyy.y2;
      d0 = *pt0;
      d1 = *pt1;
      ENDP(pt1);
      ENDP(pt0);
      deref_head(d0, call_bfunc_yy_unk);
    call_bfunc_yy_nvar:
      deref_head(d1, call_bfunc_yy2_unk);
    call_bfunc_yy2_nvar:
      if (IsIntTerm(d0) && IsIntTerm(d1)) {
      int flags;

      Int v = IntOfTerm(d0) - IntOfTerm(d1);
      flags = PREG->u.llyy.flags;
      if (v > 0) {
        if (flags & GT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llyy);
          JMPNext();
        } else {
          PREG = PREG->u.llyy.f;
          JMPNext();
        }
      } else if (v < 0) {
        if (flags & LT_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llyy);
          JMPNext();
        } else {
          PREG = PREG->u.llyy.f;
          JMPNext();
        }
      } else /* if (v == 0) */ {
        if (flags & EQ_OK_IN_CMP) {
          PREG = NEXTOP(PREG, llyy);
          JMPNext();
        } else {
          PREG = PREG->u.llyy.f;
          JMPNext();
        }
      }
      } 
    exec_bin_cmp_yy:
      {
      CmpPredicate f = PREG->u.llyy.p->cs.d_code;
      saveregs();
      d0 = (CELL) (f) (d0,d1);
      }
      setregs();
      if (!d0) {
      if (PREG != FAILCODE)
        PREG = PREG->u.llyy.f;
      JMPNext();
      }
      PREG = NEXTOP(PREG, llyy);
      JMPNext();

      BEGP(pt0);
      deref_body(d0, pt0, call_bfunc_yy_unk, call_bfunc_yy_nvar);
      d1 = Deref(d1);
      goto exec_bin_cmp_yy;
      ENDP(pt0);

      BEGP(pt0);
      deref_body(d1, pt0, call_bfunc_yy2_unk, call_bfunc_yy2_nvar);
      goto exec_bin_cmp_yy;
      ENDP(pt0);

      ENDD(d1);
      ENDD(d0);
      ENDBOp();

      Op(p_equal, e);
      save_hb();
      if (Yap_IUnify(ARG1, ARG2) == FALSE) {
      FAIL();
      }
      PREG = NEXTOP(PREG, e);
      GONext();
      ENDOp();

      Op(p_dif, l);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("\\="),2),0)),XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      BEGD(d1);
      d0 = ARG1;
      deref_head(d0, dif_unk1);
    dif_nvar1:
      /* first argument is bound */
      d1 = ARG2;
      deref_head(d1, dif_nvar1_unk2);
    dif_nvar1_nvar2:
      /* both arguments are bound */
      if (d0 == d1) {
      PREG = PREG->u.l.l;
      GONext();
      }
      if (IsAtomOrIntTerm(d0) || IsAtomOrIntTerm(d1)) {
      PREG = NEXTOP(PREG, l);
      GONext();
      }
      {
      Int opresult;
#ifdef COROUTINING
      /*
       * We may wake up goals during our attempt to unify the
       * two terms. If we are adding to the tail of a list of
       * woken goals that should be ok, but otherwise we need
       * to restore WokenGoals to its previous value.
       */
      CELL OldWokenGoals = Yap_ReadTimedVar(WokenGoals);

#endif
      /* We will have to look inside compound terms */
      register tr_fr_ptr pt0;
      /* store the old value of TR for clearing bindings */
      pt0 = TR;
      BEGCHO(pt1);
      pt1 = B;
      /* make B and HB point to H to guarantee all bindings will
       * be trailed
       */
      HBREG = H;
      B = (choiceptr) H;
      SET_BB(B);
      save_hb();
      opresult = Yap_IUnify(d0, d1);
#ifdef COROUTINING
      /* now restore Woken Goals to its old value */
      Yap_UpdateTimedVar(WokenGoals, OldWokenGoals);
      if (OldWokenGoals == TermNil) {
        Yap_undo_signal(YAP_WAKEUP_SIGNAL);
      }
#endif
      /* restore B */
      B = pt1;
      SET_BB(PROTECT_FROZEN_B(pt1));
#ifdef COROUTINING
      H = HBREG;
#endif
      HBREG = B->cp_h;
      /* untrail all bindings made by Yap_IUnify */
      while (TR != pt0) {
        BEGD(d1);
        d1 = TrailTerm(--TR);
        if (IsVarTerm(d1)) {
#if defined(SBA) && defined(YAPOR)
          /* clean up the trail when we backtrack */
          if (Unsigned((Int)(d1)-(Int)(H_FZ)) >
            Unsigned((Int)(B_FZ)-(Int)(H_FZ))) {
            RESET_VARIABLE(STACK_TO_SBA(d1));
          } else
#endif
            /* normal variable */
            RESET_VARIABLE(d1);
#ifdef MULTI_ASSIGNMENT_VARIABLES
        } else /* if (IsApplTerm(d1)) */ {
          CELL *pt = RepAppl(d1);
          /* AbsAppl means */
          /* multi-assignment variable */
          /* so the next cell is the old value */ 
#ifdef FROZEN_STACKS
          pt[0] = TrailVal(--TR);
#else
          pt[0] = TrailTerm(--TR);
          TR--;
#endif /* FROZEN_STACKS */
#endif /* MULTI_ASSIGNMENT_VARIABLES */
        }
        ENDD(d1);
      }
      if (opresult) {
        /* restore B, no need to restore HB */
        PREG = PREG->u.l.l;
        GONext();
      }
      /* restore B, and later HB */
      PREG = NEXTOP(PREG, l);
      ENDCHO(pt1);
      }
      GONext();

      BEGP(pt0);
      deref_body(d0, pt0, dif_unk1, dif_nvar1);
      ENDP(pt0);
      /* first argument is unbound */
      PREG = PREG->u.l.l;
      GONext();

      BEGP(pt0);
      deref_body(d1, pt0, dif_nvar1_unk2, dif_nvar1_nvar2);
      ENDP(pt0);
      /* second argument is unbound */
      PREG = PREG->u.l.l;
      GONext();
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_eq, l);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("=="),2),0)),XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      BEGD(d1);
      d0 = ARG1;
      deref_head(d0, p_eq_unk1);
    p_eq_nvar1:
      /* first argument is bound */
      d1 = ARG2;
      deref_head(d1, p_eq_nvar1_unk2);
    p_eq_nvar1_nvar2:
      /* both arguments are bound */
      if (d0 == d1) {
      PREG = NEXTOP(PREG, l);
      GONext();
      }
      if (IsPairTerm(d0)) {
      if (!IsPairTerm(d1)) {
        PREG = PREG->u.l.l;
        GONext();
      }
      BEGD(d2);
      always_save_pc();
      d2 = iequ_complex(RepPair(d0)-1, RepPair(d0)+1,RepPair(d1)-1);
      if (d2 == FALSE) {
        PREG = PREG->u.l.l;
        GONext();
      }
      ENDD(d2);
      always_set_pc();
      PREG = NEXTOP(PREG, l);
      GONext();
      }
      if (IsApplTerm(d0)) {
      Functor f0 = FunctorOfTerm(d0);
      Functor f1;

      /* f1 must be a compound term, even if it is a suspension */
      if (!IsApplTerm(d1)) {
        PREG = PREG->u.l.l;
        GONext();
      }
      f1 = FunctorOfTerm(d1);

      /* we now know f1 is true */
      /* deref if a compound term */
      if (IsExtensionFunctor(f0)) {
        switch ((CELL)f0) {
        case (CELL)FunctorDBRef:
          if (d0 == d1) {
            PREG = NEXTOP(PREG, l);
            GONext();
          }
          PREG = PREG->u.l.l;
          GONext();
        case (CELL)FunctorLongInt:
          if (f1 != FunctorLongInt) {
            PREG = PREG->u.l.l;
            GONext();
          }
          if (LongIntOfTerm(d0) == LongIntOfTerm(d1)) {
            PREG = NEXTOP(PREG, l);
            GONext();
          }
          PREG = PREG->u.l.l;
          GONext();
#ifdef USE_GMP
        case (CELL)FunctorBigInt:
          if (f1 != FunctorBigInt) {
            PREG = PREG->u.l.l;
            GONext();
          }
          if (mpz_cmp(Yap_BigIntOfTerm(d0), Yap_BigIntOfTerm(d1)) == 0) {
            PREG = NEXTOP(PREG, l);
            GONext();
          }
          PREG = PREG->u.l.l;
          GONext();
#endif
        case (CELL)FunctorDouble:
          if (f1 != FunctorDouble) {
            PREG = PREG->u.l.l;
            GONext();
          }
          if (FloatOfTerm(d0) == FloatOfTerm(d1)) {
            PREG = NEXTOP(PREG, l);
            GONext();
          }
        default:
          PREG = PREG->u.l.l;
          GONext();
        }
      }
      if (f0 != f1) {
        PREG = PREG->u.l.l;
        GONext();
      }
      always_save_pc();
      BEGD(d2);
      d2 = iequ_complex(RepAppl(d0), RepAppl(d0)+ArityOfFunctor(f0), RepAppl(d1));
      if (d2 == FALSE) {
        PREG = PREG->u.l.l;
        GONext();
      }
      ENDD(d2);
      PREG = NEXTOP(PREG, l);
      always_set_pc();
      GONext();
      }
      PREG = PREG->u.l.l;
      GONext();

      BEGP(pt0);
      deref_body(d1, pt0, p_eq_nvar1_unk2, p_eq_nvar1_nvar2);
      ENDP(pt0);
      /* first argument is bound */
      /* second argument is unbound */
      /* I don't need to worry about co-routining because an
       unbound variable may never be == to a constrained variable!! */
      PREG = PREG->u.l.l;
      GONext();
      ENDD(d1);

      BEGP(pt0);
      deref_body(d0, pt0, p_eq_unk1, p_eq_nvar1);
      BEGD(d1);
      d1 = ARG2;
      deref_head(d1, p_eq_var1_unk2);
    p_eq_var1_nvar2:
      /* I don't need to worry about co-routining because an
       unbound variable may never be == to a constrained variable!! */
      PREG = PREG->u.l.l;
      GONext();

      BEGP(pt1);
      deref_body(d1, pt1, p_eq_var1_unk2, p_eq_var1_nvar2);
      /* first argument is unbound */
      /* second argument is unbound */
      if (pt1 != pt0) {
      PREG = PREG->u.l.l;
      GONext();
      }
      PREG = NEXTOP(PREG, l);
      GONext();      
      ENDP(pt1);
      ENDD(d1);
      ENDP(pt0);

      ENDD(d0);
      ENDOp();

      Op(p_arg_vv, xxx);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      H[0] = XREG(PREG->u.xxx.x1);
      H[1] = XREG(PREG->u.xxx.x2);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("arg"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = XREG(PREG->u.xxx.x1);
      deref_head(d0, arg_arg1_unk);
    arg_arg1_nvar:
      /* ARG1 is ok! */
      if (IsIntTerm(d0))
      d0 = IntOfTerm(d0);
      else if (IsLongIntTerm(d0)) {
      d0 = LongIntOfTerm(d0);
      } else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,d0,"arg 1 of arg/3");
      setregs();
      FAIL();
      }

      /* d0 now got the argument we want */
      BEGD(d1);
      d1 = XREG(PREG->u.xxx.x2);
      deref_head(d1, arg_arg2_unk);
    arg_arg2_nvar:
      /* d1 now got the structure we want to fetch the argument
       * from */
      if (IsApplTerm(d1)) {
      BEGP(pt0);
      pt0 = RepAppl(d1);
      d1 = *pt0;
      if (IsExtensionFunctor((Functor) d1)) {
        FAIL();
      }
      if ((Int)d0 <= 0 ||
          (Int)d0 > ArityOfFunctor((Functor) d1)) {
        /* don't complain here for Prolog compatibility 
        if ((Int)d0 <= 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");        
          setregs();
        }
        */
        FAIL();
      }
      XREG(PREG->u.xxx.x) = pt0[d0];
      PREG = NEXTOP(PREG, xxx);
      GONext();
      ENDP(pt0);
      }
      else if (IsPairTerm(d1)) {
      BEGP(pt0);
      pt0 = RepPair(d1);
      if (d0 != 1 && d0 != 2) {
        if ((Int)d0 < 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");
          setregs();
        }
        FAIL();
      }
      XREG(PREG->u.xxx.x) = pt0[d0-1];
      PREG = NEXTOP(PREG, xxx);
      GONext();
      ENDP(pt0);
      }
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_COMPOUND, d1, "arg 2 of arg/3");
      setregs();
      FAIL();
      }

      BEGP(pt0);
      deref_body(d1, pt0, arg_arg2_unk, arg_arg2_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1,"arg 2 of arg/3");;
      setregs();
      ENDP(pt0);
      FAIL();
      ENDD(d1);

      BEGP(pt0);
      deref_body(d0, pt0, arg_arg1_unk, arg_arg1_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "arg 1 of arg/3");;
      setregs();
      ENDP(pt0);
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_arg_cv, xxc);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      CELL *Ho = H;
      Term t = MkIntegerTerm(PREG->u.xxc.c); 
      H[0] =  t;
      H[1] = XREG(PREG->u.xxc.xi);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("arg"),3),0)),H);
      H = Ho;
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = PREG->u.xxc.c;
      /* d0 now got the argument we want */
      BEGD(d1);
      d1 = XREG(PREG->u.xxc.xi);
      deref_head(d1, arg_arg2_vc_unk);
    arg_arg2_vc_nvar:
      /* d1 now got the structure we want to fetch the argument
       * from */
      if (IsApplTerm(d1)) {
      BEGP(pt0);
      pt0 = RepAppl(d1);
      d1 = *pt0;
      if (IsExtensionFunctor((Functor) d1)) {
        FAIL();
      }
      if ((Int)d0 <= 0 ||
          (Int)d0 > ArityOfFunctor((Functor) d1)) {
        /* don't complain here for Prolog compatibility 
        if ((Int)d0 <= 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");        
          setregs();
        }
        */
        FAIL();
      }
      XREG(PREG->u.xxc.x) = pt0[d0];
      PREG = NEXTOP(PREG, xxc);
      GONext();
      ENDP(pt0);
      }
      else if (IsPairTerm(d1)) {
      BEGP(pt0);
      pt0 = RepPair(d1);
      if (d0 != 1 && d0 != 2) {
        if ((Int)d0 < 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");
          setregs();
        }
        FAIL();
      }
      XREG(PREG->u.xxc.x) = pt0[d0-1];
      PREG = NEXTOP(PREG, xxc);
      GONext();
      ENDP(pt0);
      }
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_COMPOUND, d1, "arg 2 of arg/3");
      setregs();
      FAIL();
      }

      BEGP(pt0);
      deref_body(d1, pt0, arg_arg2_vc_unk, arg_arg2_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1,"arg 2 of arg/3");;
      setregs();
      ENDP(pt0);
      FAIL();
      ENDD(d1);

      ENDD(d0);
      ENDOp();

      Op(p_arg_y_vv, yxx);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      H[0] = XREG(PREG->u.yxx.x1);
      H[1] = XREG(PREG->u.yxx.x2);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("arg"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = XREG(PREG->u.yxx.x1);
      deref_head(d0, arg_y_arg1_unk);
    arg_y_arg1_nvar:
      /* ARG1 is ok! */
      if (IsIntTerm(d0))
      d0 = IntOfTerm(d0);
      else if (IsLongIntTerm(d0)) {
      d0 = LongIntOfTerm(d0);
      } else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,d0,"arg 1 of arg/3");
      setregs();
      FAIL();
      }

      /* d0 now got the argument we want */
      BEGD(d1);
      d1 = XREG(PREG->u.yxx.x2);
      deref_head(d1, arg_y_arg2_unk);
    arg_y_arg2_nvar:
      /* d1 now got the structure we want to fetch the argument
       * from */
      if (IsApplTerm(d1)) {
      BEGP(pt0);
      pt0 = RepAppl(d1);
      d1 = *pt0;
      if (IsExtensionFunctor((Functor) d1)) {
        FAIL();
      }
      if ((Int)d0 <= 0 ||
          (Int)d0 > ArityOfFunctor((Functor) d1)) {
        /* don't complain here for Prolog compatibility 
        if ((Int)d0 <= 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");        
          saveregs();
        }
        */
        FAIL();
      }
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,pt0[d0]);
#else
      *pt1 = pt0[d0];
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      ENDP(pt0);
      }
      else if (IsPairTerm(d1)) {
      BEGP(pt0);
      pt0 = RepPair(d1);
      if (d0 != 1 && d0 != 2) {
        if ((Int)d0 < 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");
          setregs();
        }
        FAIL();
      }
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(PREG, yxx);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,pt0[d0-1]);
#else
      *pt1 = pt0[d0-1];
#endif /* SBA && FROZEN_STACKS */
      GONext();
      ENDP(pt1);
      ENDP(pt0);
      }
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_COMPOUND, d1, "arg 2 of arg/3");
      setregs();
      FAIL();
      }

      BEGP(pt0);
      deref_body(d1, pt0, arg_y_arg2_unk, arg_y_arg2_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1,"arg 2 of arg/3");;
      setregs();
      ENDP(pt0);
      FAIL();
      ENDD(d1);

      BEGP(pt0);
      deref_body(d0, pt0, arg_y_arg1_unk, arg_y_arg1_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "arg 1 of arg/3");;
      setregs();
      ENDP(pt0);
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_arg_y_cv, xxc);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      CELL *Ho = H;
      Term t = MkIntegerTerm(PREG->u.yxc.c); 
      H[0] =  t;
      H[1] = XREG(PREG->u.yxc.xi);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("arg"),3),0)),H);
      H = Ho;
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = PREG->u.yxc.c;
      /* d0 now got the argument we want */
      BEGD(d1);
      d1 = XREG(PREG->u.yxc.xi);
      deref_head(d1, arg_y_arg2_vc_unk);
    arg_y_arg2_vc_nvar:
      /* d1 now got the structure we want to fetch the argument
       * from */
      if (IsApplTerm(d1)) {
      BEGP(pt0);
      pt0 = RepAppl(d1);
      d1 = *pt0;
      if (IsExtensionFunctor((Functor) d1)) {
        FAIL();
      }
      if ((Int)d0 <= 0 ||
          (Int)d0 > ArityOfFunctor((Functor) d1)) {
        /* don't complain here for Prolog compatibility 
        if ((Int)d0 <= 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");        
          setregs();
        }
        */
        FAIL();
      }
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,pt0[d0]);
#else
      *pt1 = pt0[d0];
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      ENDP(pt0);
      }
      else if (IsPairTerm(d1)) {
      BEGP(pt0);
      pt0 = RepPair(d1);
      if (d0 != 1 && d0 != 2) {
        if ((Int)d0 < 0) {
          saveregs();
          Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,
              MkIntegerTerm(d0),"arg 1 of arg/3");
          setregs();
        }
        FAIL();
      }
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(PREG, yxc);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,pt0[d0-1]);
#else
      *pt1 = pt0[d0-1];
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      ENDP(pt0);
      }
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_COMPOUND, d1, "arg 2 of arg/3");
      setregs();
      FAIL();
      }

      BEGP(pt0);
      deref_body(d1, pt0, arg_y_arg2_vc_unk, arg_y_arg2_vc_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1,"arg 2 of arg/3");;
      setregs();
      ENDP(pt0);
      FAIL();
      ENDD(d1);

      ENDD(d0);
      ENDOp();

      Op(p_func2s_vv, xxx);
      /* A1 is a variable */
    restart_func2s:
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      RESET_VARIABLE(H);
      H[1] = XREG(PREG->u.xxx.x1);
      H[2] = XREG(PREG->u.xxx.x2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      /* We have to build the structure */
      BEGD(d0);
      d0 = XREG(PREG->u.xxx.x1);
      deref_head(d0, func2s_unk);
    func2s_nvar:
      /* we do, let's get the third argument */
      BEGD(d1);
      d1 = XREG(PREG->u.xxx.x2);
      deref_head(d1, func2s_unk2);
    func2s_nvar2:
      /* Uuuff, the second and third argument are bound */
      if (IsIntegerTerm(d1))
      d1 = IntegerOfTerm(d1);
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,d1,"functor/3");
      setregs();
      FAIL();
      }
      if (!IsAtomicTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xxx),sla),l);
      GONext();
      }
      else if ((Int)d1 > 0) {
      /* now let's build a compound term */
      if (!IsAtomTerm(d0)) {
        saveregs();
        Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
        setregs();
        FAIL();
      }
      BEGP(pt1);
      if (!IsAtomTerm(d0)) {
        FAIL();
      }
      else
        d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
        /* make sure we have something to show for our trouble */
        saveregs();
        if (!Yap_gc(0, YREG, NEXTOP(NEXTOP(PREG,xxx),sla))) {
          Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
          setregs();
          JMPNext();
        } else {
          setregs();
        }
        goto restart_func2s;
      }
      while ((Int)d1--) {
        RESET_VARIABLE(pt1);
        pt1++;
      }
      H = pt1;
      /* done building the term */
      ENDP(pt1);
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xxx),sla),l);
      GONext();
      }     else if ((Int)d1  == 0) {
      XREG(PREG->u.xxx.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xxx),sla),l);
      GONext();
      }     else {
      saveregs();
      Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,MkIntegerTerm(d1),"functor/3");
      setregs();
      FAIL();
      }

      BEGP(pt1);
      deref_body(d1, pt1, func2s_unk2, func2s_nvar2);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, third argument was unbound */
      FAIL();
      ENDD(d1);

      BEGP(pt1);
      deref_body(d0, pt1, func2s_unk, func2s_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2s_cv, xcx);
      /* A1 is a variable */
    restart_func2s_cv:
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      RESET_VARIABLE(H);
      H[1] = PREG->u.xcx.c;
      H[2] = XREG(PREG->u.xcx.xi);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      /* We have to build the structure */
      d0 = PREG->u.xcx.c;
      /* we do, let's get the third argument */
      BEGD(d1);
      d1 = XREG(PREG->u.xcx.xi);
      deref_head(d1, func2s_unk2_cv);
    func2s_nvar2_cv:
      /* Uuuff, the second and third argument are bound */
      if (IsIntegerTerm(d1))
      d1 = IntegerOfTerm(d1);
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,d1,"functor/3");
      setregs();
      FAIL();
      }
      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      XREG(PREG->u.xcx.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xcx),sla),l);
      GONext();
      } else if ((Int)d1 > 0) {
      /* now let's build a compound term */
      if (!IsAtomTerm(d0)) {
        saveregs();
        Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
        setregs();
        FAIL();
      }
      BEGP(pt1);
      if (!IsAtomTerm(d0)) {
        FAIL();
      }
      else
        d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
        /* make sure we have something to show for our trouble */
        saveregs();
        if (!Yap_gc(0, YREG, NEXTOP(NEXTOP(PREG,xcx),sla))) {
          Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
          setregs();
          JMPNext();
        } else {
          setregs();
        }
        goto restart_func2s_cv;
      }
      while ((Int)d1--) {
        RESET_VARIABLE(pt1);
        pt1++;
      }
      /* done building the term */
      H = pt1;
      ENDP(pt1);
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      XREG(PREG->u.xcx.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xcx),sla),l);
      GONext();
      }     else if (d1  == 0) {
      XREG(PREG->u.xcx.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xcx),sla),l);
      GONext();
      }     else {
      saveregs();
      Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,MkIntegerTerm(d1),"functor/3");
      setregs();
      FAIL();
      }

      BEGP(pt1);
      deref_body(d1, pt1, func2s_unk2_cv, func2s_nvar2_cv);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, third argument was unbound */
      FAIL();
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_func2s_vc, xxc);
      /* A1 is a variable */
    restart_func2s_vc:
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      Term ti;
      CELL *hi = H;

      ti = MkIntegerTerm((Int)(PREG->u.xxc.c));
      RESET_VARIABLE(H);
      H[1] = XREG(PREG->u.xxc.xi);
      H[2] = ti;
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      H = hi;
      }
#endif      /* LOW_LEVEL_TRACE */
      /* We have to build the structure */
      BEGD(d0);
      d0 = XREG(PREG->u.xxc.xi);
      deref_head(d0, func2s_unk_vc);
    func2s_nvar_vc:
      BEGD(d1);
      d1 = PREG->u.xxc.c;
      if (!IsAtomicTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xxc),sla),l);
      GONext();
      }
      /* now let's build a compound term */
      if (d1 == 0) {
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xxc),sla),l);
      GONext();
      }
      if (!IsAtomTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      BEGP(pt1);
      if (!IsAtomTerm(d0)) {
      FAIL();
      }
      else
      d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
      /* make sure we have something to show for our trouble */
      saveregs();
      if (!Yap_gc(0, YREG, NEXTOP(NEXTOP(PREG,xxc),sla))) {
        Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
        setregs();
        JMPNext();
      } else {
        setregs();
      }
      goto restart_func2s_vc;
      }
      while ((Int)d1--) {
      RESET_VARIABLE(pt1);
      pt1++;
      }
      /* done building the term */
      H = pt1;
      ENDP(pt1);
      ENDD(d1);
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      XREG(PREG->u.xxc.x) = d0;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, xxc),sla),l);
      GONext();

      BEGP(pt1);
      deref_body(d0, pt1, func2s_unk_vc, func2s_nvar_vc);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2s_y_vv, yxx);
      /* A1 is a variable */
    restart_func2s_y:
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      RESET_VARIABLE(H);
      H[1] = XREG(PREG->u.yxx.x1);
      H[2] = XREG(PREG->u.yxx.x2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      /* We have to build the structure */
      BEGD(d0);
      d0 = XREG(PREG->u.yxx.x1);
      deref_head(d0, func2s_y_unk);
    func2s_y_nvar:
      /* we do, let's get the third argument */
      BEGD(d1);
      d1 = XREG(PREG->u.yxx.x2);
      deref_head(d1, func2s_y_unk2);
    func2s_y_nvar2:
      /* Uuuff, the second and third argument are bound */
      if (IsIntegerTerm(d1))
      d1 = IntegerOfTerm(d1);
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,d1,"functor/3");
      setregs();
      FAIL();
      }
      if (!IsAtomicTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxx),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      } else if ((Int)d1 > 0) {
      /* now let's build a compound term */
      if (!IsAtomTerm(d0)) {
        saveregs();
        Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
        setregs();
        FAIL();
      }
      BEGP(pt1);
      if (!IsAtomTerm(d0)) {
        FAIL();
      }
      else
        d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
        /* make sure we have something to show for our trouble */
        saveregs();
        if (!Yap_gc(0, YREG, NEXTOP(NEXTOP(PREG,yxx),sla))) {
          Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
          setregs();
          JMPNext();
        } else {
          setregs();
        }
        goto restart_func2s_y;
      }
      while ((Int)d1--) {
        RESET_VARIABLE(pt1);
        pt1++;
      }
      /* done building the term */
      H = pt1;
      ENDP(pt1);
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxx),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }     else if (d1  == 0) {
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxx.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxx),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }     else {
      saveregs();
      Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,MkIntegerTerm(d1),"functor/3");
      setregs();
      FAIL();
      }

      BEGP(pt1);
      deref_body(d1, pt1, func2s_y_unk2, func2s_y_nvar2);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, third argument was unbound */
      FAIL();
      ENDD(d1);

      BEGP(pt1);
      deref_body(d0, pt1, func2s_y_unk, func2s_y_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2s_y_cv, ycx);
      /* A1 is a variable */
    restart_func2s_y_cv:
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      RESET_VARIABLE(H);
      H[1] = PREG->u.ycx.c;
      H[2] = XREG(PREG->u.ycx.xi);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      /* We have to build the structure */
      BEGD(d0);
      d0 = PREG->u.ycx.c;
      /* we do, let's get the third argument */
      BEGD(d1);
      d1 = XREG(PREG->u.ycx.xi);
      deref_head(d1, func2s_y_unk_cv);
    func2s_y_nvar_cv:
      /* Uuuff, the second and third argument are bound */
      if (IsIntegerTerm(d1)) {
      d1 = IntegerOfTerm(d1);
      } else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,d1,"functor/3");
      setregs();
      FAIL();
      }
      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      BEGP(pt1);
      pt1 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, ycx),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }
      else if ((Int)d1 > 0) {
      /* now let's build a compound term */
      if (!IsAtomTerm(d0)) {
        saveregs();
        Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
        setregs();
        FAIL();
      }
      if (!IsAtomTerm(d0)) {
        FAIL();
      }
      else
        d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      BEGP(pt1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
        /* make sure we have something to show for our trouble */
        saveregs();
        if (!Yap_gc(0, YREG, NEXTOP(NEXTOP(PREG,ycx),sla))) {
          Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
          setregs();
          JMPNext();
        } else {
          setregs();
        }
        goto restart_func2s_y_cv;
      }
      while ((Int)d1--) {
        RESET_VARIABLE(pt1);
        pt1++;
      }
      /* done building the term */
      H = pt1;
      ENDP(pt1);
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      BEGP(pt1);
      pt1 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, ycx),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }     else if (d1  == 0) {
      BEGP(pt1);
      pt1 = YREG + PREG->u.ycx.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, ycx),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }     else {
      saveregs();
      Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,MkIntegerTerm(d1),"functor/3");
      setregs();
      FAIL();
      }

      BEGP(pt1);
      deref_body(d1, pt1, func2s_y_unk_cv, func2s_y_nvar_cv);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, third argument was unbound */
      FAIL();
      ENDD(d1);
      ENDD(d0);
      ENDOp();

      Op(p_func2s_y_vc, yxc);
      /* A1 is a variable */
    restart_func2s_y_vc:
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      Term ti;
      CELL *hi = H;

      ti = MkIntegerTerm((Int)(PREG->u.yxc.c));
      RESET_VARIABLE(H);
      H[1] = XREG(PREG->u.yxc.xi);
      H[2] = ti;
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      H = hi;
      }
#endif      /* LOW_LEVEL_TRACE */
      /* We have to build the structure */
      BEGD(d0);
      d0 = XREG(PREG->u.yxc.xi);
      deref_head(d0, func2s_y_unk_vc);
    func2s_y_nvar_vc:
      BEGD(d1);
      d1 = PREG->u.yxc.c;
      if (!IsAtomicTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxc),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }
      if (d1 == 0) {
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxc),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      GONext();
      }
      if (!IsAtomTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      /* now let's build a compound term */
      if (!IsAtomTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }
      BEGP(pt1);
      if (!IsAtomTerm(d0)) {
      FAIL();
      }
      else 
      d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
      /* make sure we have something to show for our trouble */
      saveregs();
      if (!Yap_gc(0, YREG, NEXTOP(NEXTOP(PREG,yxc),sla))) {
        Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
        setregs();
        JMPNext();
      } else {
        setregs();
      }
      goto restart_func2s_y_vc;
      }
      while ((Int)d1--) {
      RESET_VARIABLE(pt1);
      pt1++;
      }
      /* done building the term */
      H = pt1;
      ENDP(pt1);
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      BEGP(pt1);
      pt1 = YREG + PREG->u.yxc.y;
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, yxc),sla),l);
#if defined(SBA) && defined(FROZEN_STACKS)
      Bind_Local(pt1,d0);
#else
      *pt1 = d0;
#endif /* SBA && FROZEN_STACKS */
      ENDP(pt1);
      ENDD(d1);
      GONext();

      BEGP(pt1);
      deref_body(d0, pt1, func2s_y_unk_vc, func2s_y_nvar_vc);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2f_xx, xxx);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      H[0] = XREG(PREG->u.xxx.x);
      RESET_VARIABLE(H+1);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = XREG(PREG->u.xxx.x);
      deref_head(d0, func2f_xx_unk);
    func2f_xx_nvar:
      if (IsApplTerm(d0)) {
      Functor d1 = FunctorOfTerm(d0);
      if (IsExtensionFunctor(d1)) {
        XREG(PREG->u.xxx.x1) = d0;
        XREG(PREG->u.xxx.x2) = MkIntTerm(0);
        PREG = NEXTOP(PREG, xxx);
        GONext();
      }
      XREG(PREG->u.xxx.x1) = MkAtomTerm(NameOfFunctor(d1));
      XREG(PREG->u.xxx.x2) = MkIntegerTerm(ArityOfFunctor(d1));
      PREG = NEXTOP(PREG, xxx);
      GONext();
      } else if (IsPairTerm(d0)) {
      XREG(PREG->u.xxx.x1) = TermDot;
      XREG(PREG->u.xxx.x2) = MkIntTerm(2);
      PREG = NEXTOP(PREG, xxx);
      GONext();
      } else {
      XREG(PREG->u.xxx.x1) = d0;
      XREG(PREG->u.xxx.x2) = MkIntTerm(0);
      PREG = NEXTOP(PREG, xxx);
      GONext();
      }

      BEGP(pt1);
      deref_body(d0, pt1, func2f_xx_unk, func2f_xx_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2f_xy, xyx);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      H[0] = XREG(PREG->u.xyx.x);
      RESET_VARIABLE(H+1);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = XREG(PREG->u.xyx.x);
      deref_head(d0, func2f_xy_unk);
    func2f_xy_nvar:
      if (IsApplTerm(d0)) {
      Functor d1 = FunctorOfTerm(d0);
      CELL *pt0 = YREG+PREG->u.xyx.y2;
      if (IsExtensionFunctor(d1)) {
        XREG(PREG->u.xyx.x1) = d0;
        PREG = NEXTOP(PREG, xyx);
        *pt0 = MkIntTerm(0);
        GONext();
      }
      XREG(PREG->u.xyx.x1) = MkAtomTerm(NameOfFunctor(d1));
      PREG = NEXTOP(PREG, xyx);
      *pt0 = MkIntegerTerm(ArityOfFunctor(d1));
      GONext();
      } else if (IsPairTerm(d0)) {
      CELL *pt0 = YREG+PREG->u.xyx.y2;
      XREG(PREG->u.xyx.x1) = TermDot;
      PREG = NEXTOP(PREG, xyx);
      *pt0 = MkIntTerm(2);
      GONext();
      } else {
      CELL *pt0 = YREG+PREG->u.xyx.y2;
      XREG(PREG->u.xyx.x1) = d0;
      PREG = NEXTOP(PREG, xyx);
      *pt0 = MkIntTerm(0);
      GONext();
      }

      BEGP(pt1);
      deref_body(d0, pt1, func2f_xy_unk, func2f_xy_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2f_yx, yxx);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      H[0] = XREG(PREG->u.yxx.x2);
      RESET_VARIABLE(H+1);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = XREG(PREG->u.yxx.x2);
      deref_head(d0, func2f_yx_unk);
    func2f_yx_nvar:
      if (IsApplTerm(d0)) {
      Functor d1 = FunctorOfTerm(d0);
      CELL *pt0 = YREG+PREG->u.yxx.y;
      if (IsExtensionFunctor(d1)) {
        XREG(PREG->u.yxx.x1) = MkIntTerm(0);
        PREG = NEXTOP(PREG, yxx);
        *pt0 = d0;
        GONext();
      }
      XREG(PREG->u.yxx.x1) = MkIntegerTerm(ArityOfFunctor(d1));
      PREG = NEXTOP(PREG, yxx);
      *pt0 = MkAtomTerm(NameOfFunctor(d1));
      GONext();
      } else if (IsPairTerm(d0)) {
      CELL *pt0 = YREG+PREG->u.yxx.y;
      XREG(PREG->u.yxx.x1) = MkIntTerm(2);
      PREG = NEXTOP(PREG, yxx);
      *pt0 = TermDot;
      GONext();
      } else {
      CELL *pt0 = YREG+PREG->u.yxx.y;
      XREG(PREG->u.yxx.x1) = MkIntTerm(0);
      PREG = NEXTOP(PREG, yxx);
      *pt0 = d0;
      GONext();
      }

      BEGP(pt1);
      deref_body(d0, pt1, func2f_yx_unk, func2f_yx_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_func2f_yy, yyx);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace) {
      H[0] = XREG(PREG->u.yyx.x);
      RESET_VARIABLE(H+1);
      RESET_VARIABLE(H+2);
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),H);
      }
#endif      /* LOW_LEVEL_TRACE */
      BEGD(d0);
      d0 = XREG(PREG->u.yyx.x);
      deref_head(d0, func2f_yy_unk);
    func2f_yy_nvar:
      if (IsApplTerm(d0)) {
      Functor d1 = FunctorOfTerm(d0);
      CELL *pt0 = YREG+PREG->u.yyx.y1;
      CELL *pt1 = YREG+PREG->u.yyx.y2;
      if (IsExtensionFunctor(d1)) {
        PREG = NEXTOP(PREG, yyx);
        *pt0 =  d0;
        *pt1 = MkIntTerm(0);
        GONext();
      }
      PREG = NEXTOP(PREG, yyx);
      *pt0 = MkAtomTerm(NameOfFunctor(d1));
      *pt1 = MkIntegerTerm(ArityOfFunctor(d1));
      GONext();
      } else if (IsPairTerm(d0)) {
      CELL *pt0 = YREG+PREG->u.yyx.y1;
      CELL *pt1 = YREG+PREG->u.yyx.y2;
      PREG = NEXTOP(PREG, yyx);
      *pt0 = TermDot;
      *pt1 = MkIntTerm(2);
      GONext();
      } else {
      CELL *pt0 = YREG+PREG->u.yyx.y1;
      CELL *pt1 = YREG+PREG->u.yyx.y2;
      PREG = NEXTOP(PREG, yyx);
      *pt0 = d0;
      *pt1 = MkIntTerm(0);
      GONext();
      }

      BEGP(pt1);
      deref_body(d0, pt1, func2f_yy_unk, func2f_yy_nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDD(d0);
      ENDOp();

      Op(p_functor, e);
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
      low_level_trace(enter_pred,RepPredProp(Yap_GetPredPropByFunc(Yap_MkFunctor(Yap_LookupAtom("functor"),3),0)),XREGS+1);
#endif      /* LOW_LEVEL_TRACE */
      restart_functor:
      BEGD(d0);
      d0 = ARG1;
      deref_head(d0, func_unk);
    func_nvar:
      /* A1 is bound */
      BEGD(d1);
      if (IsApplTerm(d0)) {
      d1 = *RepAppl(d0);
      if (IsExtensionFunctor((Functor) d1)) {
        if (d1 <= (CELL)FunctorDouble && d1 >= (CELL)FunctorLongInt ) {
          d1 = MkIntTerm(0);
        } else
          FAIL();
      } else {
          d0 = MkAtomTerm(NameOfFunctor((Functor) d1));
          d1 = MkIntTerm(ArityOfFunctor((Functor) d1));
      }
      }
      else if (IsPairTerm(d0)) {
      d0 = TermDot;
      d1 = MkIntTerm(2);
      }
      else {
      d1 = MkIntTerm(0);
      }
      /* d1 and d0 now have the two arguments */
      /* let's go and bind them */
      {
      register CELL arity = d1;

      d1 = ARG2;
      deref_head(d1, func_nvar_unk);
      func_nvar_nvar:
      /* A2 was bound */
      if (d0 != d1) {
        FAIL();
      }
      /* I have to this here so that I don't have a jump to a closing bracket */
      d0 = arity;
      goto func_bind_x3;

      BEGP(pt0);
      deref_body(d1, pt0, func_nvar_unk, func_nvar_nvar);
      /* A2 is a variable, go and bind it */
      BIND(pt0, d0, bind_func_nvar_var);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
      bind_func_nvar_var:
#endif
      /* I have to this here so that I don't have a jump to a closing bracket */
      d0 = arity;
      ENDP(pt0);
      func_bind_x3:
      /* now let's process A3 */
      d1 = ARG3;
      deref_head(d1, func_nvar3_unk);
      func_nvar3_nvar:
      /* A3 was bound */
      if (d0 != d1) {
        FAIL();
      }
      /* Done */
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, e),sla),l);
      GONext();

      BEGP(pt0);
      deref_body(d1, pt0, func_nvar3_unk, func_nvar3_nvar);
      /* A3 is a variable, go and bind it */
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, e),sla),l);
      BIND(pt0, d0, bind_func_nvar3_var);
      /* Done */
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
      bind_func_nvar3_var:
#endif
      GONext();


      ENDP(pt0);

      }
      ENDD(d1);

      BEGP(pt0);
      deref_body(d0, pt0, func_unk, func_nvar);
      /* A1 is a variable */
      /* We have to build the structure */
      d0 = ARG2;
      deref_head(d0, func_var_2unk);
    func_var_2nvar:
      /* we do, let's get the third argument */
      BEGD(d1);
      d1 = ARG3;
      deref_head(d1, func_var_3unk);
    func_var_3nvar:
      /* Uuuff, the second and third argument are bound */
      if (IsIntTerm(d1))
      d1 = IntOfTerm(d1);
      else {
      saveregs();
      Yap_Error(TYPE_ERROR_INTEGER,ARG3,"functor/3");
      setregs();
      FAIL();
      }
      if (!IsAtomicTerm(d0)) {
      saveregs();
      Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
      setregs();
      FAIL();
      }      /* We made it!!!!! we got in d0 the name, in d1 the arity and
       * in pt0 the variable to bind it to. */
      if (d0 == TermDot && d1 == 2) {
      RESET_VARIABLE(H);
      RESET_VARIABLE(H+1);
      d0 = AbsPair(H);
      H += 2;
      }
      else if ((Int)d1 > 0) {
      /* now let's build a compound term */
      if (!IsAtomTerm(d0)) {
        saveregs();
        Yap_Error(TYPE_ERROR_ATOM,d0,"functor/3");
        setregs();
        FAIL();
      }
      BEGP(pt1);
      if (!IsAtomTerm(d0)) {
        FAIL();
      }
      else
        d0 = (CELL) Yap_MkFunctor(AtomOfTerm(d0), (Int) d1);
      pt1 = H;
      *pt1++ = d0;
      d0 = AbsAppl(H);
      if (pt1+d1 > ENV || pt1+d1 > (CELL *)B) {
        /* make sure we have something to show for our trouble */
        saveregs();
        if (!Yap_gc(3, YREG, NEXTOP(NEXTOP(PREG,e),sla))) {
          Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
          setregs();
          JMPNext();
        } else {
          setregs();
        }
        goto restart_functor;
      }
      while ((Int)d1--) {
        RESET_VARIABLE(pt1);
        pt1++;
      }
      /* done building the term */
      H = pt1;
      ENDP(pt1);
      }     else if ((Int)d1  < 0) {
      saveregs();
      Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO,MkIntegerTerm(d1),"functor/3");
      setregs();
      FAIL();
      }
      /* else if arity is 0 just pass d0 through */
      /* Ding, ding, we made it */
      PREG = NEXTOP(NEXTOP(NEXTOP(PREG, e),sla),l);
      BIND(pt0, d0, bind_func_var_3nvar);
#ifdef COROUTINING
      DO_TRAIL(pt0, d0);
      if (pt0 < H0) Yap_WakeUp(pt0);
    bind_func_var_3nvar:
#endif
      GONext();


      BEGP(pt1);
      deref_body(d1, pt1, func_var_3unk, func_var_3nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d1, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, third argument was unbound */
      FAIL();
      ENDD(d1);

      BEGP(pt1);
      deref_body(d0, pt1, func_var_2unk, func_var_2nvar);
      saveregs();
      Yap_Error(INSTANTIATION_ERROR, d0, "functor/3");
      setregs();
      ENDP(pt1);
      /* Oops, second argument was unbound too */
      FAIL();
      ENDP(pt0);
      ENDD(d0);
      ENDOp();

      BOp(p_execute, sla);
      { 
      PredEntry *pen;
      Term mod = PREG->u.sla.sla_u.mod;

      CACHE_Y_AS_ENV(YREG);
      /* Try to preserve the environment */
      ENV_YREG = (CELL *) (((char *) YREG) + PREG->u.sla.s);
#ifdef FROZEN_STACKS
      { 
        choiceptr top_b = PROTECT_FROZEN_B(B);
#ifdef SBA
        if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
        if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif /* SBA */
      }
#else
      if (ENV_YREG > (CELL *) B) {
        ENV_YREG = (CELL *) B;
      }
#endif /* FROZEN_STACKS */
      BEGD(d0);
      d0 = ARG1;
      restart_execute:
      deref_head(d0, execute_unk);
      execute_nvar:
      if (IsApplTerm(d0)) {
        Functor f = FunctorOfTerm(d0);
        if (IsExtensionFunctor(f)) {
          goto execute_metacall;
        }
        pen = RepPredProp(PredPropByFunc(f, mod));
        if (pen->PredFlags & (MetaPredFlag|GoalExPredFlag)) {
          if (f == FunctorModule) {
            Term tmod = ArgOfTerm(1,d0);
            if (!IsVarTerm(tmod) && IsAtomTerm(tmod)) {
            d0 = ArgOfTerm(2,d0);
            mod = tmod;
            goto execute_nvar;
            }
          } else if (f == FunctorComma) {
            SREG = RepAppl(d0);
            BEGD(d1);
            d1 = SREG[2];
            /* create an to execute the call */
            deref_head(d1, execute_comma_unk);
          execute_comma_nvar:
            if (IsAtomTerm(d1)) {
            ENV_YREG[-EnvSizeInCells-2]  = MkIntegerTerm((Int)PredPropByAtom(AtomOfTerm(d1),mod));
            ENV_YREG[-EnvSizeInCells-3]  = mod;
            } else if (IsApplTerm(d1)) {
            Functor f = FunctorOfTerm(d1);
            if (IsExtensionFunctor(f)) {
              goto execute_metacall;
            } else {
              if (f == FunctorModule) goto execute_metacall;
              ENV_YREG[-EnvSizeInCells-2]  = MkIntegerTerm((Int)PredPropByFunc(f,mod));
              ENV_YREG[-EnvSizeInCells-3]  = mod;
            }
            } else {
            goto execute_metacall;
            }
            ENV_YREG[E_CP] = (CELL)NEXTOP(PREG,sla);
            ENV_YREG[E_CB] = (CELL)B;
            ENV_YREG[E_E]  = (CELL)ENV;
#ifdef DEPTH_LIMIT
            ENV_YREG[E_DEPTH] = DEPTH;
#endif      /* DEPTH_LIMIT */
            ENV_YREG[-EnvSizeInCells-1]  = d1;
            ENV = ENV_YREG;
            ENV_YREG -= EnvSizeInCells+3;
            PREG = COMMA_CODE;
            /* for profiler */
            save_pc();
            d0 = SREG[1];
            goto restart_execute;

            BEGP(pt1);
            deref_body(d1, pt1, execute_comma_unk, execute_comma_nvar);
            goto execute_metacall;
            ENDP(pt1);
            ENDD(d1);
          } else if (mod != CurrentModule) {
            goto execute_metacall;
          }
        }
        if (PRED_GOAL_EXPANSION_ALL) {
          goto execute_metacall;
        }

        BEGP(pt1);
        pt1 = RepAppl(d0);
        BEGD(d2);
        for (d2 = ArityOfFunctor(f); d2; d2--) {
#if SBA
          BEGD(d1);
          d1 = pt1[d2];
          if (d1 == 0) {
            XREGS[d2] = (CELL)(pt1+d2);
          } else {
            XREGS[d2] = d1;
          }
#else
          XREGS[d2] = pt1[d2];
#endif
        }
        ENDD(d2);
        ENDP(pt1);
        CACHE_A1();
      } else if (IsAtomTerm(d0)) {
        if (PRED_GOAL_EXPANSION_ALL) {
          goto execute_metacall;
        } else {
          pen = RepPredProp(PredPropByAtom(AtomOfTerm(d0), mod));
        }
      } else {
        goto execute_metacall;
      }

      execute_end:
      /* code copied from call */
#ifndef NO_CHECKING
      check_stack(NoStackPExecute, H);
#endif
      CPREG = NEXTOP(PREG, sla);
      ALWAYS_LOOKAHEAD(pen->OpcodeOfPred);
      PREG = pen->CodeOfPred;
      /* for profiler */
      save_pc();
#ifdef DEPTH_LIMIT
      if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is primitives */
        if (pen->ModuleOfPred) {
          if (DEPTH == MkIntTerm(0))
            FAIL();
          else DEPTH = RESET_DEPTH();
        }
      } else if (pen->ModuleOfPred)
        DEPTH -= MkIntConstant(2);
#endif      /* DEPTH_LIMIT */
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
        low_level_trace(enter_pred,pen,XREGS+1);
#endif      /* LOW_LEVEL_TRACER */
      WRITEBACK_Y_AS_ENV();
      /* setup GB */
      ENV_YREG[E_CB] = (CELL) B;
#ifdef YAPOR
      SCH_check_requests();
#endif      /* YAPOR */
      CACHE_A1();
      ALWAYS_GONext();
      ALWAYS_END_PREFETCH();

      BEGP(pt1);
      deref_body(d0, pt1, execute_unk, execute_nvar);
       execute_metacall:
      ARG1 = ARG3 = d0;
      pen = PredMetaCall;
      ARG2 = Yap_cp_as_integer(B);
      if (mod)
        ARG4 = mod;
      else
        ARG4 = TermProlog;
      goto execute_end;
      ENDP(pt1);

      ENDD(d0);
      NoStackPExecute:
      SREG = (CELL *) pen;
      ASP = ENV_YREG;
      /* setup GB */
      WRITEBACK_Y_AS_ENV();
      YREG[E_CB] = (CELL) B;
      if (ActiveSignals) {
        goto creep_pe;
      }
      saveregs_and_ycache();
      if (!Yap_gc(((PredEntry *)SREG)->ArityOfPE, ENV, NEXTOP(PREG, sla))) {
        Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs_and_ycache();
      goto execute_end;
      ENDCACHE_Y_AS_ENV();
      }
      ENDBOp();

    creep_pe:                 /* do creep in call                                     */
      CPREG = NEXTOP(PREG, sla);
      goto creep;

      BOp(p_execute_tail, sla);
      {
      PredEntry *pen;
      Term mod;
      UInt arity;

      CACHE_Y_AS_ENV(YREG);
      BEGP(pt0);
      BEGD(d0);
      d0 = ENV_YREG[-EnvSizeInCells-1];
      pen = RepPredProp((Prop)IntegerOfTerm(ENV_YREG[-EnvSizeInCells-2]));
      CPREG = (yamop *) ENV_YREG[E_CP];
      pt0 = ENV_YREG;
      ENV_YREG = ENV = (CELL *) ENV_YREG[E_E];
#ifdef FROZEN_STACKS
      { 
        choiceptr top_b = PROTECT_FROZEN_B(B);

#ifdef SBA
        if (ENV_YREG > (CELL *) top_b || ENV_YREG < H) ENV_YREG = (CELL *) top_b;
#else
        if (ENV_YREG > (CELL *) top_b) ENV_YREG = (CELL *) top_b;
#endif /* SBA */
        else ENV_YREG = (CELL *)((CELL)ENV_YREG + ENV_Size(CPREG));
      }
#else
      if (ENV_YREG > (CELL *)B) {
        ENV_YREG = (CELL *)B;
      } else {
        ENV_YREG = (CELL *) ((CELL) ENV_YREG+ ENV_Size(CPREG));
      }
#endif /* FROZEN_STACKS */
      arity = pen->ArityOfPE;
      if (pen->PredFlags & (MetaPredFlag|GoalExPredFlag)) {
        mod = pt0[-EnvSizeInCells-3];
        if (pen->FunctorOfPred == FunctorComma) {
          SREG = RepAppl(d0);
          BEGD(d1);
          d1 = SREG[2];
        execute_comma_comma:
          /* create an to execute the call */
          deref_head(d1, execute_comma_comma_unk);
        execute_comma_comma_nvar:
          ENV_YREG[E_CB] = (CELL)pt0[E_CB];
          if (IsAtomTerm(d1)) {
            ENV_YREG[-EnvSizeInCells-2]  = MkIntegerTerm((Int)PredPropByAtom(AtomOfTerm(d1),mod));
          } else if (IsApplTerm(d1)) {
            Functor f = FunctorOfTerm(d1);
            if (IsExtensionFunctor(f)) {
            goto execute_metacall_after_comma;
            } else if (f == FunctorModule) {
            Term tmod = ArgOfTerm(1, d1);
            if (IsVarTerm(tmod) || !IsAtomTerm(tmod))
              goto execute_metacall_after_comma;
            mod = tmod;
            d1 = RepAppl(d1)[2];
            goto execute_comma_comma;
            } else {
            ENV_YREG[-EnvSizeInCells-2]  = MkIntegerTerm((Int)PredPropByFunc(f,mod));
            }
          } else {
            goto execute_metacall_after_comma;
          }
          ENV_YREG[E_CP] = (CELL)CPREG;
          ENV_YREG[E_E]  = (CELL)ENV;
#ifdef DEPTH_LIMIT
          ENV_YREG[E_DEPTH] = DEPTH;
#endif      /* DEPTH_LIMIT */
          ENV_YREG[-EnvSizeInCells-1]  = d1;
          ENV_YREG[-EnvSizeInCells-3]  = mod;
          ENV = ENV_YREG;
          ENV_YREG -= EnvSizeInCells+3;
          d0 = SREG[1];
          CPREG = NEXTOP(COMMA_CODE,sla);
        execute_comma_comma2:
          /* create an to execute the call */
          deref_head(d0, execute_comma_comma2_unk);
        execute_comma_comma2_nvar:
          if (IsAtomTerm(d0)) {
            Atom at = AtomOfTerm(d0);
            arity = 0;
            if (at == AtomCut) {
            choiceptr cut_pt = (choiceptr)pt0[E_CB];
#ifdef CUT_C
            {
              if (SHOULD_CUT_UP_TO(B,(choiceptr) cut_pt))
                {
                  while (POP_CHOICE_POINT(cut_pt))
                  {
                    POP_EXECUTE();
                  }
                }
            }
#endif /* CUT_C */
#ifdef YAPOR
            CUT_prune_to(cut_pt);
#endif /* YAPOR */
            /* find where to cut to */
            if (SHOULD_CUT_UP_TO(B,cut_pt)) {
              /* Wow, we're gonna cut!!! */
#ifdef TABLING
              while (B->cp_b < cut_pt) {
                B = B->cp_b;
              }
              abolish_incomplete_subgoals(B);
#endif /* TABLING */
              B = cut_pt;
              HB = PROTECT_FROZEN_H(B);
            }
            }
            pen = RepPredProp(PredPropByAtom(at, mod));
            goto execute_comma;
          } else if (IsApplTerm(d0)) {
            Functor f = FunctorOfTerm(d0);
            if (IsExtensionFunctor(f) || f == FunctorModule) {
            Term tmod = ArgOfTerm(1, d0);
            if (IsVarTerm(tmod) || !IsAtomTerm(tmod))
              goto execute_metacall_after_comma;
            mod = tmod;
            d0 = RepAppl(d0)[2];
            goto execute_comma_comma2;
            } else {
            pen = RepPredProp(PredPropByFunc(f,mod));
            if (pen->PredFlags & (MetaPredFlag|GoalExPredFlag)) {
              goto execute_metacall_after_comma;
            }
            arity = pen->ArityOfPE;
            goto execute_comma;
            }
          } else {
            if (mod != CurrentModule)
            goto execute_metacall_after_comma;
            else {
            arity = pen->ArityOfPE;
            goto execute_comma;
            }
          }

          BEGP(pt1);
          deref_body(d0, pt1, execute_comma_comma2_unk, execute_comma_comma2_nvar);
          goto execute_metacall_after_comma;
          ENDP(pt1);

          BEGP(pt1);
          deref_body(d1, pt1, execute_comma_comma_unk, execute_comma_comma_nvar);
          goto execute_metacall_after_comma;
          ENDP(pt1);
          ENDD(d1);
        } else {
          if (mod != CurrentModule) {
            execute_metacall_after_comma:
            ARG1 = ARG3 = d0;
            pen = PredMetaCall;
            ARG2 = Yap_cp_as_integer((choiceptr)pt0[E_CB]);
            if (mod)
            ARG4 = mod;
            else
            ARG4 = TermProlog;
            CACHE_A1();
            goto execute_after_comma;
          }
        }
      }
      execute_comma:
      if (arity) {
        BEGP(pt1);
        pt1 = RepAppl(d0);
        BEGD(d2);
        for (d2 = arity; d2; d2--) {
#if SBA
          BEGD(d1);
          d1 = pt1[d2];
          if (d1 == 0)
            XREGS[d2] = (CELL)(pt1+d2);
          else
            XREGS[d2] = d1;
#else
          XREGS[d2] = pt1[d2];
#endif
        }
        ENDD(d2);
        ENDP(pt1);
        CACHE_A1();
      } else if ((Atom)(pen->FunctorOfPred) == AtomCut) {
        choiceptr cut_pt = (choiceptr)pt0[E_CB];
#ifdef CUT_C
        {
          if (SHOULD_CUT_UP_TO(B,(choiceptr) cut_pt))
            {
            while (POP_CHOICE_POINT(cut_pt))
              {
                POP_EXECUTE();
              }
            }
        }
#endif /* CUT_C */
#ifdef YAPOR
        CUT_prune_to(cut_pt);
#endif /* YAPOR */
        /* find where to cut to */
        if (SHOULD_CUT_UP_TO(B,cut_pt)) {
          /* Wow, we're gonna cut!!! */
#ifdef TABLING
          while (B->cp_b < cut_pt) {
            B = B->cp_b;
          }
          abolish_incomplete_subgoals(B);
#endif /* TABLING */
          B = cut_pt;
          HB = PROTECT_FROZEN_H(B);
        }
      }

      execute_after_comma:
#ifndef NO_CHECKING
      check_stack(NoStackPTExecute, H);
#endif
      PREG = pen->CodeOfPred;
      /* for profiler */
      save_pc();
      ALWAYS_LOOKAHEAD(pen->OpcodeOfPred);
      ENV_YREG[E_CB] = (CELL)B;
#ifdef LOW_LEVEL_TRACER
      if (Yap_do_low_level_trace)
        low_level_trace(enter_pred,pen,XREGS+1);
#endif      /* LOW_LEVEL_TRACER */
#ifdef DEPTH_LIMIT
      if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is primitives */
        if (pen->ModuleOfPred) {
          if (DEPTH == MkIntTerm(0))
            FAIL();
          else DEPTH = RESET_DEPTH();
        }
      } else if (pen->ModuleOfPred) {
        DEPTH -= MkIntConstant(2);
      }
#endif      /* DEPTH_LIMIT */
      /* do deallocate */
      WRITEBACK_Y_AS_ENV();
      ALWAYS_GONext();
      ALWAYS_END_PREFETCH();

      ENDD(d0);
      ENDP(pt0);
      NoStackPTExecute:
      WRITEBACK_Y_AS_ENV();
      SREG = (CELL *) pen;
      ASP = ENV_YREG;
      if (ASP > (CELL *)PROTECT_FROZEN_B(B))
        ASP = (CELL *)PROTECT_FROZEN_B(B);
      LOCK(SignalLock);
      UNLOCK(SignalLock);
      if (ActiveSignals & YAP_CDOVF_SIGNAL) {
        saveregs_and_ycache();
        if (!Yap_growheap(FALSE, 0, NULL)) {
          Yap_Error(OUT_OF_HEAP_ERROR, TermNil, "YAP failed to grow heap: %s", Yap_ErrorMessage);
          setregs_and_ycache();
          FAIL();
        }
        setregs_and_ycache();
        LOCK(SignalLock);
        ActiveSignals &= ~YAP_CDOVF_SIGNAL;
        CreepFlag = CalculateStackGap();
        UNLOCK(SignalLock);
        if (!ActiveSignals) {
          goto execute_after_comma;
        }
      }
      if (ActiveSignals & YAP_TROVF_SIGNAL) {
#if SHADOW_S
        S = SREG;
#endif
        saveregs_and_ycache();
        if(!Yap_growtrail (sizeof(CELL) * 16 * 1024L, FALSE)) {
          Yap_Error(OUT_OF_TRAIL_ERROR,TermNil,"YAP failed to reserve %ld bytes in growtrail",sizeof(CELL) * 16 * 1024L);
          setregs_and_ycache();
          FAIL();
        }
        setregs_and_ycache();
        LOCK(SignalLock);
        ActiveSignals &= ~YAP_TROVF_SIGNAL;
        CreepFlag = CalculateStackGap();
        UNLOCK(SignalLock);
        if (!ActiveSignals) {
          goto execute_after_comma;
        }
      }
      if (ActiveSignals) {
        if (ActiveSignals & YAP_CDOVF_SIGNAL) {
          goto noheapleft;
        }
        goto creep;
      }
      saveregs();
      if (!Yap_gc(((PredEntry *)SREG)->ArityOfPE, ENV, NEXTOP(PREG, sla))) {
        Yap_Error(OUT_OF_STACK_ERROR,TermNil,Yap_ErrorMessage);
      }
      setregs();
      goto execute_after_comma;
      ENDCACHE_Y_AS_ENV();

      }
      ENDBOp();

#if !USE_THREADED_CODE
    default:
      saveregs();
      Yap_Error(SYSTEM_ERROR, MkIntegerTerm(opcode), "trying to execute invalid YAAM instruction %d", opcode);
      setregs();
      FAIL();
    }
  }
#endif

#if USE_THREADED_CODE
#if PUSH_REGS
  restore_absmi_regs(old_regs);
#endif
#if BP_FREE
  P1REG = PCBACKUP;
#endif
  return (0);
#endif

}

int        STD_PROTO(Yap_absmiEND,(void));

/* dummy function that is needed for profiler */
int Yap_absmiEND(void)
{
  return 1;
}

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