diff --git a/C/absmi.c b/C/absmi.c
index 322325230..63b2802bd 100644
--- a/C/absmi.c
+++ b/C/absmi.c
@@ -10,8 +10,11 @@
 *									 *
 * File:		absmi.c							 *
 * comments:	Portable abstract machine interpreter                    *
-* Last rev:     $Date: 2005-11-15 00:50:49 $,$Author: vsc $						 *
+* Last rev:     $Date: 2005-11-18 18:48:51 $,$Author: tiagosoares $						 *
 * $Log: not supported by cvs2svn $
+* 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.
 *
@@ -267,11 +270,16 @@
 *									 *
 *************************************************************************/
 
+
 #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)) {
@@ -1431,6 +1439,14 @@ Yap_absmi(int inp)
 
       /* 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;
@@ -1741,6 +1757,17 @@ Yap_absmi(int inp)
       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 */
@@ -1917,6 +1944,17 @@ Yap_absmi(int inp)
       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 */
@@ -1959,6 +1997,17 @@ Yap_absmi(int inp)
       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 */
@@ -2020,6 +2069,17 @@ Yap_absmi(int inp)
 #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 */
@@ -2055,6 +2115,17 @@ Yap_absmi(int inp)
 #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 */
@@ -6863,6 +6934,10 @@ Yap_absmi(int inp)
       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);
@@ -6879,9 +6954,22 @@ Yap_absmi(int inp)
 	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) {
@@ -6914,11 +7002,26 @@ Yap_absmi(int inp)
       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);
@@ -6940,6 +7043,13 @@ Yap_absmi(int inp)
       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) {
@@ -6971,7 +7081,19 @@ Yap_absmi(int inp)
       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             				 *
 \************************************************************************/
@@ -8391,6 +8513,17 @@ Yap_absmi(int inp)
 #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 */
@@ -8439,6 +8572,17 @@ Yap_absmi(int inp)
 #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 */
@@ -12431,6 +12575,17 @@ Yap_absmi(int inp)
 	      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 */
@@ -12522,6 +12677,17 @@ Yap_absmi(int inp)
 	  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 */
diff --git a/C/c_interface.c b/C/c_interface.c
index 161d608e9..410358088 100644
--- a/C/c_interface.c
+++ b/C/c_interface.c
@@ -10,8 +10,11 @@
 * File:		c_interface.c						 *
 * comments:	c_interface primitives definition 			 *
 *									 *
-* Last rev:	$Date: 2005-11-03 18:49:26 $,$Author: vsc $						 *
+* Last rev:	$Date: 2005-11-18 18:48:51 $,$Author: tiagosoares $						 *
 * $Log: not supported by cvs2svn $
+* Revision 1.76  2005/11/03 18:49:26  vsc
+* fix bignum conversion
+*
 * Revision 1.75  2005/10/28 17:38:49  vsc
 * sveral updates
 *
@@ -190,6 +193,10 @@
 #include "or.macros.h"
 #endif	/* YAPOR */
 #include "threads.h"
+#ifdef CUT_C
+#include "cut_c.h"
+#endif /* CUT_C */
+
 
 #define YAP_BOOT_FROM_PROLOG       0
 #define YAP_BOOT_FROM_SAVED_CODE   1
@@ -286,6 +293,10 @@ X_API void    STD_PROTO(YAP_PredicateInfo,(void *,Atom *,unsigned long int *,Ter
 X_API void    STD_PROTO(YAP_UserCPredicate,(char *,CPredicate,unsigned long int));
 X_API void    STD_PROTO(YAP_UserBackCPredicate,(char *,CPredicate,CPredicate,unsigned long int,unsigned int));
 X_API void    STD_PROTO(YAP_UserCPredicateWithArgs,(char *,CPredicate,unsigned long int,Term));
+#ifdef CUT_C
+X_API void    STD_PROTO(YAP_UserBackCutCPredicate,(char *,CPredicate,CPredicate,CPredicate,unsigned long int,unsigned int));
+X_API void   *STD_PROTO(YAP_ExtraSpaceCut,(void));
+#endif
 X_API Term     STD_PROTO(YAP_CurrentModule,(void));
 X_API Term     STD_PROTO(YAP_CreateModule,(Atom));
 X_API int     STD_PROTO(YAP_ThreadSelf,(void));
@@ -614,6 +625,20 @@ YAP_ArityOfFunctor(Functor f)
   return (ArityOfFunctor(f));
 }
 
+#ifdef CUT_C
+X_API void *
+YAP_ExtraSpaceCut(void)
+{
+  void *ptr;
+  BACKUP_B();
+
+  ptr = (void *)(((CELL *)(Yap_regp->CUT_C_TOP))-(((yamop *)Yap_regp->CUT_C_TOP->try_userc_cut_yamop)->u.lds.extra));
+
+  RECOVER_B();
+  return(ptr);
+}
+#endif /*CUT_C*/
+
 X_API void *
 YAP_ExtraSpace(void)
 {
@@ -631,7 +656,14 @@ X_API void
 YAP_cut_up(void)
 {
   BACKUP_B();
-
+#ifdef CUT_C
+      {
+	while (POP_CHOICE_POINT(B->cp_b))
+	  { 
+	    POP_EXECUTE();
+	  }
+      }
+#endif /* CUT_C */
 #ifdef YAPOR
   {
     choiceptr cut_pt;
@@ -1463,9 +1495,24 @@ X_API void
 YAP_UserBackCPredicate(char *name, CPredicate init, CPredicate cont,
 		   unsigned long int arity, unsigned int extra)
 {
+#ifdef CUT_C
+  Yap_InitCPredBackCut(name, arity, extra, init, cont, NULL ,UserCPredFlag);
+#else
   Yap_InitCPredBack(name, arity, extra, init, cont, UserCPredFlag);
+#endif
+
 }
 
+#ifdef CUT_C
+X_API void 
+YAP_UserBackCutCPredicate(char *name, CPredicate init, CPredicate cont, CPredicate cut,
+			  unsigned long int arity, unsigned int extra)
+{
+  Yap_InitCPredBackCut(name, arity, extra, init, cont, cut, UserCPredFlag);
+}
+#endif
+
+
 X_API void
 YAP_UserCPredicateWithArgs(char *a, CPredicate f, unsigned long int arity, Term mod)
 {
diff --git a/C/cut_c.c b/C/cut_c.c
new file mode 100755
index 000000000..dfd455621
--- /dev/null
+++ b/C/cut_c.c
@@ -0,0 +1,34 @@
+#ifdef CUT_C
+
+#include "Yap.h"
+#include "cut_c.h"
+#include <stdio.h>
+
+void cut_c_initialize(void){
+  Yap_regp->CUT_C_TOP=(cut_c_str_ptr)Yap_LocalBase;
+}
+
+/*Removes a choice_point from the stack*/
+void cut_c_pop(void){
+  cut_c_str_ptr to_delete = NULL;
+  if (((int)Yap_regp->CUT_C_TOP) == ((int)Yap_LocalBase))
+    {
+      return;
+    }
+  else
+    { /* removes the top element
+	 from the stack */
+      to_delete = Yap_regp->CUT_C_TOP;
+      Yap_regp->CUT_C_TOP = to_delete->before;
+      return;
+    }
+}
+
+/*Insert a choice_point in the stack*/
+void cut_c_push(cut_c_str_ptr new_top){
+  new_top->before = Yap_regp->CUT_C_TOP;
+  Yap_regp->CUT_C_TOP=new_top;
+  return;
+}
+
+#endif /*CUT_C*/
diff --git a/C/exec.c b/C/exec.c
index ba21b9ef2..b8a5ee39b 100644
--- a/C/exec.c
+++ b/C/exec.c
@@ -20,6 +20,9 @@ static char     SccsId[] = "@(#)cdmgr.c	1.1 05/02/98";
 
 #include "absmi.h"
 #include "yapio.h"
+#ifdef CUT_C
+#include "cut_c.h"
+#endif
 
 STATIC_PROTO(Int  CallPredicate, (PredEntry *, choiceptr, yamop *));
 STATIC_PROTO(Int  EnterCreepMode, (Term, Term));
@@ -1404,6 +1407,16 @@ Yap_execute_goal(Term t, int nargs, Term mod)
     /* restore the old environment */
     /* get to previous environment */
     cut_B = (choiceptr)ENV[E_CB];
+#ifdef CUT_C
+    {
+      /* Note that 
+	 cut_B == (choiceptr)ENV[E_CB] */
+      while (POP_CHOICE_POINT(ENV[E_CB]))
+	{
+	  POP_EXECUTE();
+	}
+    }
+#endif /* CUT_C */
 #ifdef YAPOR
     CUT_prune_to(cut_B);
 #endif /* YAPOR */
@@ -1592,6 +1605,14 @@ p_restore_regs2(void)
 #else
   pt0 = (choiceptr)(LCL0-IntOfTerm(d0));
 #endif
+#ifdef CUT_C
+  {
+    while (POP_CHOICE_POINT(pt0))
+      {
+	POP_EXECUTE();
+      }
+  }
+#endif /* CUT_C */
 #ifdef YAPOR
   CUT_prune_to(pt0);
 #endif /* YAPOR */
diff --git a/C/grow.c b/C/grow.c
index ac48f1377..76fb1ff4c 100644
--- a/C/grow.c
+++ b/C/grow.c
@@ -23,6 +23,9 @@
 #include "sshift.h"
 #include "compile.h"
 #include "attvar.h"
+#ifdef CUT_C
+#include "cut_c.h"
+#endif /* CUT_C */
 #if HAVE_STRING_H
 #include <string.h>
 #endif
@@ -131,6 +134,10 @@ SetHeapRegs(void)
     HB = PtoGloAdjust(HB);
   if (B)
     B = ChoicePtrAdjust(B);
+#ifdef CUT_C
+  if (Yap_regp->CUT_C_TOP)
+    Yap_regp->CUT_C_TOP = (cut_c_str_ptr)ChoicePtrAdjust((choiceptr)Yap_regp->CUT_C_TOP);
+#endif
 #ifdef TABLING
   if (B_FZ)
     B_FZ = ChoicePtrAdjust(B_FZ);
@@ -190,6 +197,10 @@ SetStackRegs(void)
     LCL0 = PtoLocAdjust(LCL0);
   if (B)
     B = ChoicePtrAdjust(B);
+#ifdef CUT_C
+  if (Yap_regp->CUT_C_TOP)
+    Yap_regp->CUT_C_TOP = (cut_c_str_ptr)ChoicePtrAdjust((choiceptr)Yap_regp->CUT_C_TOP);
+#endif
 #ifdef TABLING
   if (B_FZ)
     B_FZ = ChoicePtrAdjust(B_FZ);
diff --git a/C/index.c b/C/index.c
index 80a36501c..9f4e4bc17 100644
--- a/C/index.c
+++ b/C/index.c
@@ -11,8 +11,11 @@
 * File:		index.c							 *
 * comments:	Indexing a Prolog predicate				 *
 *									 *
-* Last rev:     $Date: 2005-10-29 02:21:47 $,$Author: vsc $						 *
+* Last rev:     $Date: 2005-11-18 18:48:52 $,$Author: tiagosoares $						 *
 * $Log: not supported by cvs2svn $
+* Revision 1.146  2005/10/29 02:21:47  vsc
+* people should be able to disable indexing.
+*
 * Revision 1.145  2005/09/08 22:06:44  rslopes
 * BEAM for YAP update...
 *
@@ -302,6 +305,9 @@ static char     SccsId[] = "%W% %G%";
 #if HAVE_STRING_H
 #include <string.h>
 #endif
+#ifdef CUT_C
+#include "cut_c.h"
+#endif
 
 UInt STATIC_PROTO(do_index, (ClauseDef *,ClauseDef *,struct intermediates *,UInt,UInt,int,int,CELL *));
 UInt STATIC_PROTO(do_compound_index, (ClauseDef *,ClauseDef *,Term *t,struct intermediates *,UInt,UInt,UInt,UInt,int,int,int,CELL *,int));
@@ -3090,9 +3096,9 @@ groups_in(ClauseDef *min, ClauseDef *max, GroupDef *grp)
       } while (min <= max &&
 	       (!IsVarTerm(min->Tag)));
       if (min <= max && min->Tag == (_var+1)*sizeof(CELL)) {
-	  min++;
-	  if (min < max)
-	    goto restart_loop;
+	min++;
+	if (min < max)
+	  goto restart_loop;
       }
       grp->LastClause = min-1;
     }
@@ -7830,6 +7836,14 @@ Yap_FollowIndexingCode(PredEntry *ap, yamop *ipc, Term Terms[3], yamop *ap_pc, y
       ipc = NEXTOP(ipc,ld);
       break;
     case _trust:
+#ifdef CUT_C
+      {
+	while (POP_CHOICE_POINT(B->cp_b))
+	  {
+	    POP_EXECUTE();
+	  }
+      }
+#endif /* CUT_C */
 #ifdef YAPOR
       {
 	choiceptr cut_pt;
@@ -7848,6 +7862,14 @@ Yap_FollowIndexingCode(PredEntry *ap, yamop *ipc, Term Terms[3], yamop *ap_pc, y
     case _profiled_trust_me:
     case _trust_me:
     case _count_trust_me:
+#ifdef CUT_C
+      {
+	while (POP_CHOICE_POINT(B->cp_b))
+	  {
+	    POP_EXECUTE();
+	  }
+      }
+#endif /* CUT_C */
 #ifdef YAPOR
       {
 	choiceptr cut_pt;
@@ -8164,6 +8186,14 @@ Yap_FollowIndexingCode(PredEntry *ap, yamop *ipc, Term Terms[3], yamop *ap_pc, y
 	return NULL;
     default:
       if (b0) {
+#ifdef CUT_C
+      {
+	while (POP_CHOICE_POINT(B->cp_b))
+	  {
+	    POP_EXECUTE();
+	  }
+      }
+#endif /* CUT_C */
 #ifdef YAPOR
 	{
 	  choiceptr cut_pt;
@@ -8184,6 +8214,14 @@ Yap_FollowIndexingCode(PredEntry *ap, yamop *ipc, Term Terms[3], yamop *ap_pc, y
   }
   if (b0) {
     /* I did a trust */
+#ifdef CUT_C
+      {
+	while (POP_CHOICE_POINT(B->cp_b))
+	  {
+	    POP_EXECUTE();
+	  }
+      }
+#endif /* CUT_C */
 #ifdef YAPOR
     {
       choiceptr cut_pt;
diff --git a/C/init.c b/C/init.c
index 503d52a0a..416362afc 100644
--- a/C/init.c
+++ b/C/init.c
@@ -62,12 +62,17 @@ STATIC_PROTO(void  InTTYLine, (char *));
 STATIC_PROTO(void  SetOp, (int, int, char *, Term));
 STATIC_PROTO(void  InitOps, (void));
 STATIC_PROTO(void  InitDebug, (void));
+#ifdef CUT_C
+STATIC_PROTO(void  CleanBack, (PredEntry *, CPredicate, CPredicate, CPredicate));
+#else
 STATIC_PROTO(void  CleanBack, (PredEntry *, CPredicate, CPredicate));
+#endif
 STATIC_PROTO(void  InitStdPreds,(void));
 STATIC_PROTO(void  InitFlags, (void));
 STATIC_PROTO(void  InitCodes, (void));
 STATIC_PROTO(void  InitVersion, (void));
 
+
 STD_PROTO(void  exit, (int));
 
 /**************	YAP PROLOG GLOBAL VARIABLES *************************/
@@ -614,7 +619,11 @@ Yap_InitAsmPred(char *Name,  unsigned long int Arity, int code, CPredicate def,
 
 
 static void 
+#ifdef CUT_C
+CleanBack(PredEntry *pe, CPredicate Start, CPredicate Cont, CPredicate Cut)
+#else
 CleanBack(PredEntry *pe, CPredicate Start, CPredicate Cont)
+#endif
 {
   yamop   *code;
   if (pe->cs.p_code.FirstClause != pe->cs.p_code.LastClause ||
@@ -644,11 +653,43 @@ CleanBack(PredEntry *pe, CPredicate Start, CPredicate Cont)
   PUT_YAMOP_SEQ(code);
 #endif /* YAPOR */
   code->u.lds.f = Cont;
+#ifdef CUT_C
+  code = NEXTOP(code,lds);
+  if (pe->PredFlags & UserCPredFlag)
+    code->opc = Yap_opcode(_cut_c);
+  else
+    code->opc = Yap_opcode(_cut_userc);
+  code->u.lds.f = Cut;
+#endif
 }
 
 
+#ifdef CUT_C
 void 
-Yap_InitCPredBack(char *Name, unsigned long int Arity, unsigned int Extra, CPredicate Start, CPredicate Cont, int flags)
+Yap_InitCPredBack(char *Name, unsigned long int Arity,
+		  unsigned int Extra, CPredicate Start,
+		  CPredicate Cont,int flags){
+  Yap_InitCPredBack_(Name,Arity,Extra,Start,Cont,NULL,flags);
+}
+
+void
+Yap_InitCPredBackCut(char *Name, unsigned long int Arity,
+		     unsigned int Extra, CPredicate Start,
+		     CPredicate Cont,CPredicate Cut,int flags){
+  Yap_InitCPredBack_(Name,Arity,Extra,Start,Cont,Cut,flags);
+}
+#endif /* CUT_C */
+
+void
+#ifdef CUT_C 
+Yap_InitCPredBack_(char *Name, unsigned long int Arity,
+		  unsigned int Extra, CPredicate Start,
+		  CPredicate Cont, CPredicate Cut,int flags)
+#else
+Yap_InitCPredBack(char *Name, unsigned long int Arity,
+		  unsigned int Extra, CPredicate Start,
+		  CPredicate Cont, int flags)
+#endif 
 {
   PredEntry      *pe;
   Atom            atom = Yap_FullLookupAtom(Name);
@@ -658,15 +699,35 @@ Yap_InitCPredBack(char *Name, unsigned long int Arity, unsigned int Extra, CPred
   else
     pe = RepPredProp(PredPropByAtom(atom,CurrentModule));
   if (pe->cs.p_code.FirstClause != NIL)
-    CleanBack(pe, Start, Cont);
+    {
+#ifdef CUT_C
+      CleanBack(pe, Start, Cont, Cut);
+#else
+      CleanBack(pe, Start, Cont);
+#endif /*CUT_C*/
+    }
   else {
     StaticClause *cl;
     yamop      *code = ((StaticClause *)NULL)->ClCode;
-    pe->PredFlags = CompiledPredFlag | StandardPredFlag ;
+#ifdef CUT_C
+    if (flags &  UserCPredFlag) 
+      pe->PredFlags = UserCPredFlag | CompiledPredFlag | StandardPredFlag;
+    else
+      pe->PredFlags = CompiledPredFlag | StandardPredFlag;
+#else /* BUG ?*/
+    pe->PredFlags = CompiledPredFlag | StandardPredFlag;
+#endif /*CUT_C*/
+
 #ifdef YAPOR
     pe->PredFlags |= SequentialPredFlag;
 #endif /* YAPOR */
+    
+#ifdef CUT_C
+    cl = (StaticClause *)Yap_AllocCodeSpace((CELL)NEXTOP(NEXTOP(NEXTOP(NEXTOP(code,lds),lds),lds),e));
+#else
     cl = (StaticClause *)Yap_AllocCodeSpace((CELL)NEXTOP(NEXTOP(NEXTOP(code,lds),lds),e));
+#endif
+    
     if (cl == NULL) {
       Yap_Error(OUT_OF_HEAP_ERROR,TermNil,"No Heap Space in InitCPredBack");
       return;
@@ -701,6 +762,17 @@ Yap_InitCPredBack(char *Name, unsigned long int Arity, unsigned int Extra, CPred
     PUT_YAMOP_SEQ(code);
 #endif /* YAPOR */
     code = NEXTOP(code,lds);
+#ifdef CUT_C
+    if (flags & UserCPredFlag)
+      code->opc = Yap_opcode(_cut_userc);
+    else
+      code->opc = Yap_opcode(_cut_c);
+    code->u.lds.f = Cut;
+    code->u.lds.p = pe;
+    code->u.lds.s = Arity;
+    code->u.lds.extra = Extra;
+    code = NEXTOP(code,lds);
+#endif /* CUT_C */
     code->opc = Yap_opcode(_Ystop);
   }
 }
diff --git a/C/inlines.c b/C/inlines.c
index f6836c96e..6780d3700 100755
--- a/C/inlines.c
+++ b/C/inlines.c
@@ -19,6 +19,10 @@
 
 #include "absmi.h"
 
+#ifdef CUT_C
+#include "cut_c.h"
+#endif
+
 STATIC_PROTO(Int    p_atom, (void));
 STATIC_PROTO(Int    p_atomic, (void));
 STATIC_PROTO(Int    p_integer, (void));
@@ -761,6 +765,14 @@ p_cut_by( void)
 #else
   pt0 = (choiceptr)(LCL0-IntOfTerm(d0));
 #endif
+#ifdef CUT_C
+  {
+    while (POP_CHOICE_POINT(pt0))
+      {
+	POP_EXECUTE();
+      }
+  }
+#endif /* CUT_C */
 #ifdef YAPOR
     CUT_prune_to(pt0);
 #endif /* YAPOR */
diff --git a/H/Regs.h b/H/Regs.h
index a45588661..bf23a9f5c 100644
--- a/H/Regs.h
+++ b/H/Regs.h
@@ -10,11 +10,15 @@
 * File:		Regs.h							 *
 * mods:									 *
 * comments:	YAP abstract machine registers				 *
-* version:      $Id: Regs.h,v 1.30 2004-09-16 17:29:08 vsc Exp $	 *
+* version:      $Id: Regs.h,v 1.31 2005-11-18 18:50:34 tiagosoares Exp $	 *
 *************************************************************************/
 
 
 /*********  abstract machine registers **********************************/
+#ifdef CUT_C
+#include "cut_c.h"
+#endif
+
 
 #define MaxTemps	512
 
@@ -76,6 +80,9 @@ typedef struct
     tr_fr_ptr TR_;		/* 24 top of trail                            */
     CELL   *H_;			/* 25 top of heap (global)  stack             */
     choiceptr B_;		/* 26 latest choice point                     */
+#ifdef CUT_C
+    cut_c_str_ptr CUT_C_TOP;
+#endif
 #ifdef  DEPTH_LIMIT
     CELL   DEPTH_;		/* 27                                         */
 #endif  /* DEPTH_LIMIT */
diff --git a/H/YapOpcodes.h b/H/YapOpcodes.h
index 3c0a4adc2..439f6bbe9 100644
--- a/H/YapOpcodes.h
+++ b/H/YapOpcodes.h
@@ -11,8 +11,11 @@
 * File:		YapOpcodes.h						 *
 * comments:	Central Table with all YAP opcodes                       *
 *									 *
-* Last rev:     $Date: 2005-09-08 21:55:48 $							 *
+* Last rev:     $Date: 2005-11-18 18:50:34 $							 *
 * $Log: not supported by cvs2svn $
+* Revision 1.34  2005/09/08 21:55:48  rslopes
+* BEAM for YAP update...
+*
 * Revision 1.33  2005/08/01 15:40:38  ricroc
 * TABLING NEW: better support for incomplete tabling
 *
@@ -138,9 +141,15 @@
     OPCODE(try_and_mark            ,ld),
     OPCODE(retry_and_mark          ,ld),
     OPCODE(try_c                   ,lds),		
-    OPCODE(retry_c                 ,lds),		
+    OPCODE(retry_c                 ,lds),
+#ifdef CUT_C
+    OPCODE(cut_c   ,lds),
+#endif		
     OPCODE(try_userc               ,lds),		
     OPCODE(retry_userc             ,lds),		
+#ifdef CUT_C
+    OPCODE(cut_userc ,lds),
+#endif		
     OPCODE(cut                     ,e),		
     OPCODE(get_x_var               ,xx),		
     OPCODE(get_y_var               ,yx),		
diff --git a/H/Yapproto.h b/H/Yapproto.h
index 75787461f..7df9bfec0 100644
--- a/H/Yapproto.h
+++ b/H/Yapproto.h
@@ -10,7 +10,7 @@
 * File:		Yap.proto						 *
 * mods:									 *
 * comments:	Function declarations for YAP				 *
-* version:      $Id: Yapproto.h,v 1.62 2005-10-28 17:38:50 vsc Exp $	 *
+* version:      $Id: Yapproto.h,v 1.63 2005-11-18 18:50:34 tiagosoares Exp $	 *
 *************************************************************************/
 
 /* prototype file for Yap */
@@ -185,6 +185,10 @@ void	STD_PROTO(Yap_InitCPred,(char *, unsigned long int, CPredicate, int));
 void	STD_PROTO(Yap_InitAsmPred,(char *, unsigned long int, int, CPredicate, int));
 void	STD_PROTO(Yap_InitCmpPred,(char *, unsigned long int, CmpPredicate, int));
 void	STD_PROTO(Yap_InitCPredBack,(char *, unsigned long int, unsigned int, CPredicate,CPredicate,int));
+#ifdef CUT_C
+void	STD_PROTO(Yap_InitCPredBackCut,(char *, unsigned long int, unsigned int, CPredicate,CPredicate,CPredicate,int));
+void    STD_PROTO(Yap_InitCPredBack_,(char *, unsigned long int, unsigned int, CPredicate,CPredicate,CPredicate,int));
+#endif
 void	STD_PROTO(Yap_InitWorkspace,(int,int,int,int,int,int,int));
 
 #if defined(YAPOR) || defined(THREADS)
@@ -304,6 +308,7 @@ void	STD_PROTO(Yap_InitUtilCPreds,(void));
 
 /* yap.c */
 
+
 /* ypsocks.c */
 void	STD_PROTO(Yap_InitSockets,(void));
 #ifdef USE_SOCKET
diff --git a/H/cut_c.h b/H/cut_c.h
new file mode 100755
index 000000000..e8b87f0e0
--- /dev/null
+++ b/H/cut_c.h
@@ -0,0 +1,55 @@
+#ifndef __CUT_C_H__
+#define __CUT_C_H__
+
+/* Some definitions */
+#define Choice_Point_Type void *
+
+/* necessary for not redefine NULL*/
+#ifndef NULL
+#define NULL nil
+#endif
+
+typedef struct cut_c_str *cut_c_str_ptr;
+struct cut_c_str{
+  cut_c_str_ptr before;
+  void *try_userc_cut_yamop;
+};
+
+#define CUT_C_STR_SIZE ((sizeof(struct cut_c_str))/(sizeof(CELL)))
+
+#define EXTRA_CBACK_CUT_ARG(Type,Offset) \
+((Type) (*(Type *)(((CELL *)Yap_regp->CUT_C_TOP) - (((yamop *)Yap_regp->CUT_C_TOP->try_userc_cut_yamop)->u.lds.extra)) + (Offset-1)))
+
+#define CUT_C_PUSH(YAMOP,S_YREG)                                 \
+           {                                                     \
+             if ((YAMOP)->u.lds.f){                              \
+	      S_YREG = S_YREG - CUT_C_STR_SIZE;                  \
+              cut_c_str_ptr new_top = (cut_c_str_ptr) S_YREG;    \
+              new_top->try_userc_cut_yamop = YAMOP;              \
+	      cut_c_push(new_top);                               \
+	     }                                                   \
+           }
+
+
+#define POP_CHOICE_POINT(B) \
+(((int)Yap_regp->CUT_C_TOP != (int)Yap_LocalBase) && ((int)B > (int)Yap_regp->CUT_C_TOP)) 
+
+
+#define POP_EXECUTE()                                                                 \
+        cut_c_str_ptr TOP = Yap_regp->CUT_C_TOP;                                            \
+        CPredicate func = (CPredicate)((yamop *)TOP->try_userc_cut_yamop)->u.lds.f;   \
+        PredEntry *pred = (PredEntry *)((yamop *)TOP->try_userc_cut_yamop)->u.lds.p;  \
+        YAP_Execute(pred,func);                                                       \
+        cut_c_pop();
+
+
+/*Initializes CUT_C_TOP*/
+void cut_c_initialize(void);
+
+/*Removes a choice_point from the stack*/
+void cut_c_pop(void);
+
+/*Insert a choice_point in the stack*/
+void cut_c_push(cut_c_str_ptr);
+
+#endif /*_CUT_C_H__*/
diff --git a/Makefile.in b/Makefile.in
index 6140f0ec8..2fbddac8a 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -122,7 +122,8 @@ HEADERS = \
 	$(srcdir)/OPTYap/sparc_locks.h $(srcdir)/OPTYap/mips_locks.h \
 	$(srcdir)/OPTYap/mips_locks_funcs.h $(srcdir)/OPTYap/alpha_locks.h \
 	$(srcdir)/OPTYap/alpha_locks_funcs.h \
-	$(srcdir)/OPTYap/pthread_locks.h
+	$(srcdir)/OPTYap/pthread_locks.h \
+	$(srcdir)/H/cut_c.h 
 
 C_SOURCES= \
 	$(srcdir)/C/absmi.c $(srcdir)/C/adtdefs.c \
@@ -161,7 +162,8 @@ C_SOURCES= \
 	$(srcdir)/OPTYap/or.cowengine.c $(srcdir)/OPTYap/or.sbaengine.c \
 	$(srcdir)/OPTYap/or.scheduler.c $(srcdir)/OPTYap/or.cut.c \
 	$(srcdir)/OPTYap/tab.tries.c $(srcdir)/OPTYap/tab.suspend.c \
-	$(srcdir)/library/mpi/mpi.c $(srcdir)/library/mpi/mpe.c
+	$(srcdir)/library/mpi/mpi.c $(srcdir)/library/mpi/mpe.c \
+	$(srcdir)/C/cut_c.c 
 
 PL_SOURCES= \
 	$(srcdir)/pl/arith.yap $(srcdir)/pl/arrays.yap $(srcdir)/pl/boot.yap \
@@ -191,7 +193,7 @@ ENGINE_OBJECTS = \
 	agc.o absmi.o adtdefs.o alloc.o amasm.o analyst.o arrays.o \
 	arith0.o arith1.o arith2.o attvar.o bb.o \
 	cdmgr.o cmppreds.o compiler.o computils.o \
-	corout.o dbase.o dlmalloc.o errors.o eval.o bignum.o \
+	corout.o cut_c.o dbase.o dlmalloc.o errors.o eval.o bignum.o \
 	exec.o grow.o heapgc.o index.o init.o  inlines.o \
 	iopreds.o depth_bound.o mavar.o modules.o other.o   \
 	parser.o save.o scanner.o sort.o stdpreds.o sysbits.o threads.o \
@@ -282,6 +284,9 @@ computils.o: $(srcdir)/C/computils.c
 corout.o: $(srcdir)/C/corout.c
 	$(CC) -c $(CFLAGS) $(srcdir)/C/corout.c -o $@
 
+cut_c.o: $(srcdir)/C/cut_c.c
+	$(CC) -c $(CFLAGS) $(srcdir)/C/cut_c.c -o $@
+
 dbase.o: $(srcdir)/C/dbase.c
 	$(CC) -c $(CFLAGS) $(srcdir)/C/dbase.c -o $@
 
diff --git a/configure b/configure
index e3697c3dc..13d31910e 100755
--- a/configure
+++ b/configure
@@ -845,6 +845,7 @@ if test -n "$ac_init_help"; then
 Optional Features:
   --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
   --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
+--enable-cut-c             support for executing c code when a cut occurs
  --enable-tabling           support tabling
  --enable-or-parallelism    support or-parallelism as: env-copy,sba,a-cow
  --enable-depth-limit       support depth-bound computation
@@ -2262,7 +2263,13 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
-
+# Check whether --enable-cut-c was given.
+if test "${enable_cut_c+set}" = set; then
+  enableval="$enable_cut_c"
+  cut_c="$enableval"
+else
+  cut_c=no
+fi;
 # Check whether --enable-tabling or --disable-tabling was given.
 if test "${enable_tabling+set}" = set; then
   enableval="$enable_tabling"
@@ -6253,6 +6260,11 @@ case "$orparallelism" in
   ;;
 esac
 
+if test "$cut_c" = "yes"
+  then  
+  YAP_EXTRAS="$YAP_EXTRAS -DCUT_C=1"
+fi
+
 if test "$tabling" = "yes"
   then
   YAP_EXTRAS="$YAP_EXTRAS -DTABLING=1"
diff --git a/console/yap.c b/console/yap.c
index 6d7d730dc..b7a77a79a 100644
--- a/console/yap.c
+++ b/console/yap.c
@@ -19,6 +19,11 @@
 #include "config.h"
 #include "YapInterface.h"
 
+#ifdef CUT_C
+#include "cut_c.h"
+#endif
+
+
 #if (DefTrailSpace < MinTrailSpace)
 #undef DefTrailSpace
 #define DefTrailSpace	MinTrailSpace
@@ -657,7 +662,13 @@ main (int argc, char **argv)
   YAP_init_args init_args;
   int i;
 
+
   BootMode = init_standard_system(argc, argv, &init_args);
+
+#ifdef CUT_C
+  cut_c_initialize();
+#endif
+
   if (BootMode == YAP_BOOT_ERROR) {
     fprintf(stderr,"[ FATAL ERROR: could not find saved state ]\n");
     exit(1);
diff --git a/include/YapInterface.h b/include/YapInterface.h
index c9a02d444..1227cd0dd 100644
--- a/include/YapInterface.h
+++ b/include/YapInterface.h
@@ -174,9 +174,11 @@ extern X_API unsigned int PROTO(YAP_ArityOfFunctor,(YAP_Functor));
 
 /*  void ExtraSpace(void) */
 extern X_API void *PROTO(YAP_ExtraSpace,(void));
+extern X_API void *PROTO(YAP_ExtraSpaceCut,(void));
 
 #define YAP_PRESERVE_DATA(ptr, type) (ptr = (type *)YAP_ExtraSpace())
 #define YAP_PRESERVED_DATA(ptr, type) (ptr = (type *)YAP_ExtraSpace())
+#define YAP_PRESERVED_DATA_CUT(ptr,type) (ptr = (type *)YAP_ExtraSpaceCut())
 
 /*   YAP_Bool      unify(YAP_Term a, YAP_Term b) */
 extern X_API YAP_Bool PROTO(YAP_Unify,(YAP_Term, YAP_Term));
@@ -191,6 +193,10 @@ extern X_API void PROTO(YAP_UserCPredicateWithArgs,(CONST char *, YAP_Bool (*)(v
     arity, int extra) */
 extern X_API void PROTO(YAP_UserBackCPredicate,(CONST char *, YAP_Bool (*)(void), YAP_Bool (*)(void), unsigned int, unsigned int));
 
+/*  void UserBackCPredicate(char *name, int *init(), int *cont(), int *cut(), int
+    arity, int extra) */
+extern X_API void PROTO(YAP_UserBackCutCPredicate,(char *, YAP_Bool (*)(void), YAP_Bool (*)(void), YAP_Bool (*)(void), unsigned long int, unsigned int));
+
 /*  void CallProlog(YAP_Term t) */
 extern X_API YAP_Bool PROTO(YAP_CallProlog,(YAP_Term t));
 
diff --git a/include/c_interface.h b/include/c_interface.h
index 2d18ee1ce..c0c0e3227 100644
--- a/include/c_interface.h
+++ b/include/c_interface.h
@@ -178,6 +178,7 @@
 
 #define PRESERVE_DATA(ptr, type) (ptr = (type *)YAP_ExtraSpace())
 #define PRESERVED_DATA(ptr, type) (ptr = (type *)YAP_ExtraSpace())
+#define PRESERVED_DATA_CUT(ptr,type) (ptr = (type *)YAP_ExtraSpaceCut())
 
 /*   YAP_Int      unify(YAP_Term a, YAP_Term b) */
 #define unify(t1,t2)  YAP_Unify(t1, t2)