Merge /home/vsc/yap

C/cdmgr.c

@@ -2036,7 +2036,7 @@ static Int p_sys_export(USES_REGS1) { /* '$set_spy'(+Fun,+M)	 */
 
 ******************************************************************/
 
-static Int p_is_no_trace(USES_REGS1) { /* '$undefined'(P,Mod)	 */
+static Int p_is_private(USES_REGS1) { /* '$undefined'(P,Mod)	 */
   PredEntry *pe;
 
   pe = Yap_get_pred(Deref(ARG1), Deref(ARG2), "undefined/1");
@@ -2051,7 +2051,7 @@ static Int p_is_no_trace(USES_REGS1) { /* '$undefined'(P,Mod)	 */
   return false;
 }
 
-static Int p_set_no_trace(USES_REGS1) { /* '$set_no_trace'(+Fun,+M)	 */
+static Int p_set_private(USES_REGS1) { /* '$set_private'(+Fun,+M)	 */
   PredEntry *pe;
 
   pe = Yap_get_pred(Deref(ARG1), Deref(ARG2), "undefined/1");
@@ -2067,7 +2067,7 @@ int Yap_SetNoTrace(char *name, arity_t arity, Term tmod) {
   PredEntry *pe;
 
   if (arity == 0) {
-    pe = Yap_get_pred(MkAtomTerm(Yap_LookupAtom(name)), tmod, "no_trace");
+    pe = Yap_get_pred(MkAtomTerm(Yap_LookupAtom(name)), tmod, "private");
   } else {
     pe = RepPredProp(
         PredPropByFunc(Yap_MkFunctor(Yap_LookupAtom(name), arity), tmod));
@@ -4252,7 +4252,7 @@ static Int init_pred_flag_vals(USES_REGS1) {
                    ModuleTransparentPredFlag PASS_REGS);
   pred_flag_clause(f, mod, "multi", MultiFileFlag PASS_REGS);
   pred_flag_clause(f, mod, "no_spy", NoSpyPredFlag PASS_REGS);
-  pred_flag_clause(f, mod, "no_trace", NoTracePredFlag PASS_REGS);
+  pred_flag_clause(f, mod, "private", NoTracePredFlag PASS_REGS);
   pred_flag_clause(f, mod, "number_db", NumberDBPredFlag PASS_REGS);
   pred_flag_clause(f, mod, "profiled", ProfiledPredFlag PASS_REGS);
   pred_flag_clause(f, mod, "quasi_quotation", QuasiQuotationPredFlag PASS_REGS);
@@ -4331,9 +4331,9 @@ void Yap_InitCdMgr(void) {
                 SafePredFlag | SyncPredFlag);
   Yap_InitCPred("$is_discontiguous", 2, p_is_discontiguous,
                 TestPredFlag | SafePredFlag);
-  Yap_InitCPred("$is_no_trace", 2, p_is_no_trace, TestPredFlag | SafePredFlag);
+  Yap_InitCPred("$is_private", 2, p_is_private, TestPredFlag | SafePredFlag);
-  Yap_InitCPred("$set_no_trace", 2, p_set_no_trace,
+  Yap_InitCPred("$set_private", 2, p_set_private,
-                TestPredFlag | SafePredFlag);
+                SyncPredFlag | SafePredFlag);
   Yap_InitCPred("$is_profiled", 1, p_is_profiled, SafePredFlag | SyncPredFlag);
   Yap_InitCPred("$profile_info", 3, p_profile_info,
                 SafePredFlag | SyncPredFlag);

C/exec.c

@@ -792,6 +792,14 @@ restart_exec:
   return CallPredicate(RepPredProp(pe), cut_cp, code PASS_REGS);
 }
 
+static Int  creep_clause(USES_REGS1) { /* '$execute_clause'(Goal)	 */
+  Int rc =  execute_clause( PASS_REGS1 );
+  if (!LOCAL_InterruptsDisabled) {
+    Yap_signal(YAP_CREEP_SIGNAL);
+  }
+  return rc;
+}
+
 static Int execute_in_mod(USES_REGS1) { /* '$execute'(Goal)	 */
   return do_execute(Deref(ARG1), Deref(ARG2) PASS_REGS);
 }
@@ -898,6 +906,10 @@ static bool watch_cut(Term ext USES_REGS) {
   bool active = ArgOfTerm(5, task) == TermTrue;
   bool ex_mode = false;
 
+  LOCAL_Signals = 0;
+      CalculateStackGap(PASS_REGS1);
+      LOCAL_PrologMode = UserMode;
+      
   if (complete) {
     return true;
   }
@@ -945,6 +957,9 @@ static bool watch_retry(Term d0 USES_REGS) {
   bool complete = !IsVarTerm(ArgOfTerm(4, task));
   bool active = ArgOfTerm(5, task) == TermTrue;
   choiceptr B0 = (choiceptr)(LCL0 - IntegerOfTerm(ArgOfTerm(6, task)));
+      LOCAL_Signals = 0;
+      CalculateStackGap(PASS_REGS1);
+      LOCAL_PrologMode = UserMode;
 
   if (complete)
     return true;
@@ -1003,6 +1018,9 @@ static Int setup_call_catcher_cleanup(USES_REGS1) {
   Int oENV = LCL0 - ENV;
   Int oYENV = LCL0 - YENV;
   bool rc;
+      LOCAL_Signals = 0;
+      CalculateStackGap(PASS_REGS1);
+      LOCAL_PrologMode = UserMode;
   Yap_DisableInterrupts(worker_id);
   rc = Yap_RunTopGoal(Setup, false);
   Yap_EnableInterrupts(worker_id);
@@ -1038,6 +1056,9 @@ static Int cleanup_on_exit(USES_REGS1) {
   bool box = ArgOfTerm(1, task) == TermTrue;
   Term cleanup = ArgOfTerm(3, task);
   Term complete = IsNonVarTerm(ArgOfTerm(4, task));
+      LOCAL_Signals = 0;
+      CalculateStackGap(PASS_REGS1);
+      LOCAL_PrologMode = UserMode;
 
   while (B->cp_ap->opc == FAIL_OPCODE)
     B = B->cp_b;
@@ -2376,6 +2397,7 @@ void Yap_InitExecFs(void) {
   Yap_InitCPred("$execute_nonstop", 1, execute_nonstop1, NoTracePredFlag);
   Yap_InitCPred("$creep_step", 2, creep_step, NoTracePredFlag);
   Yap_InitCPred("$execute_clause", 4, execute_clause, NoTracePredFlag);
+  Yap_InitCPred("$creep_clause", 4,creep_clause, NoTracePredFlag);
   Yap_InitCPred("$current_choice_point", 1, current_choice_point, 0);
   Yap_InitCPred("$current_choicepoint", 1, current_choice_point, 0);
   CurrentModule = HACKS_MODULE;

C/globals.c

@@ -212,7 +212,7 @@ static Term NewArena(UInt size, int wid, UInt arity, CELL *where, struct cell_sp
   WORKER_REGS(wid)
 exit_cell_space(cellSpace);
     // make sure we have enough room
-    while (HR + size > ASP - MIN_ARENA_SIZE) {
+    while (HR + size > ASP - 2*MIN_ARENA_SIZE) {
       if (!Yap_gcl(size * sizeof(CELL), arity, ENV, P)) {
         Yap_ThrowError(RESOURCE_ERROR_STACK, TermNil, LOCAL_ErrorMessage);
         return TermNil;

CXX/yapi.cpp

@@ -613,6 +613,11 @@ bool YAPEngine::mgoal(Term t, Term tmod, bool release) {
   CACHE_REGS
   YAP_dogoalinfo q;
   BACKUP_MACHINE_REGS();
+<<<<<<< HEAD
+  bool rc = YAP_RunGoalOnce(t);
+  RECOVER_MACHINE_REGS();
+  return rc;
+=======
    Term *ts = nullptr;
   q.CurSlot = Yap_StartSlots();
   q.p = P;
@@ -653,6 +658,7 @@ bool YAPEngine::mgoal(Term t, Term tmod, bool release) {
   //      PyEval_RestoreThread(_save);
   RECOVER_MACHINE_REGS();
   return result;
+>>>>>>> ef3d435dec2b9606993430da2f66e06d38f3a399
 }
 /**
  * called when a query must be terminated and its state fully recovered,
@@ -674,33 +680,52 @@ Term YAPEngine::fun(Term t) {
   arity_t arity;
   Functor f;
   Atom name;
+<<<<<<< HEAD
+  YAP_dogoalinfo backup = q;
+  CELL *spt;
+  
+=======
   q.CurSlot = Yap_StartSlots();
   q.p = P;
   q.cp = CP;
 
  Int oenv = LCL0-ENV;
  Int oB = LCL0-CellPtr(B);
+>>>>>>> ef3d435dec2b9606993430da2f66e06d38f3a399
   if (IsApplTerm(t)) {
     ts = RepAppl(t) + 1;
     f = (Functor)ts[-1];
     name = NameOfFunctor(f);
     arity = ArityOfFunctor(f);
     for (arity_t i = 0; i < arity; i++)
-      XREGS[i + 1] = ts[i];
+      HR[i + 1] = ts[i];
+    arity++;
   } else if (IsAtomTerm(t)) {
     name = AtomOfTerm(t);
     f = nullptr;
-    arity = 0;
+    arity = 1;
   } else if (IsPairTerm(t)) {
-    XREGS[1] = ts[0];
+    HR[1] = ts[0];
-    XREGS[2] = ts[1];
+    HR[2] = ts[1];
-    arity = 2;
+    arity = 3;
     name = AtomDot;
     f = FunctorDot;
   } else {
     throw YAPError(SOURCE(), TYPE_ERROR_CALLABLE, t, 0);
     return 0L;
   }
+<<<<<<< HEAD
+  HR += arity+1;
+  RESET_VARIABLE(HR-1);
+  yhandle yt = Yap_InitHandle(t);
+  Term ot;
+    bool rc = YAP_RunGoalOnce(t);
+    if (rc)
+      ot = Yap_GetArg(arity,Yap_GetFromHandle(yt));
+    else
+      ot = TermNone;
+  RECOVER_MACHINE_REGS();
+=======
   Term ot = XREGS[arity + 1] = MkVarTerm();
   yhandle_t h = Yap_InitHandle(ot); 
   arity++;
@@ -729,6 +754,7 @@ Term YAPEngine::fun(Term t) {
     RECOVER_MACHINE_REGS();
     return ot;
   }
+>>>>>>> ef3d435dec2b9606993430da2f66e06d38f3a399
 }
 
 YAPQuery::YAPQuery(YAPFunctor f, YAPTerm mod, YAPTerm ts[])

library/rbtrees.yap

@@ -76,7 +76,7 @@ form colour(Left, Key, Value, Right), where _colour_  is one of =red= or
 	rb_partial_map(+,+,2,-),
 	rb_apply(+,+,2,-).
 
-
+/*
 :- use_module(library(type_check)).
 
 :- type rbtree(K,V) ---> t(tree(K,V),tree(K,V)).
@@ -97,7 +97,7 @@ form colour(Left, Key, Value, Right), where _colour_  is one of =red= or
 :- pred max(tree(K,V),K,V).
 :- pred rb_next(rbtree(K,V),K,pair(K,V),V).
 :- pred next(tree(K,V),K,pair(K,V),V,tree(K,V)).
-
+*/
 
 %%	@pred rb_new(-T) is det.
 % create an empty tree.
@@ -1455,4 +1455,4 @@ with  _NewVal_. Fails if it cannot find  _Key_ in  _T_.
 
 */
 
-%%! @}
+%%! @}

packages/python/swig/CMakeLists.txt

@@ -49,21 +49,13 @@ INCLUDE_DIRECTORIES(${PYTHON_INCLUDE_PATH}  ${CMAKE_CURRENT_BINARY_DIR}/yap4py/i
   )
 
 add_custom_command( OUTPUT  ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.cxx ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.hh 
-    COMMAND ${SWIG_EXECUTABLE} -c++  -python  -O -py3 -module "yap"  -addextern -I${CMAKE_SOURCE_DIR}/H -I${CMAKE_SOURCE_DIR}/H/generated -I${CMAKE_SOURCE_DIR}/include
+    COMMAND ${SWIG_EXECUTABLE} -c++  -python  -O -py3 -module "yap"  -addextern -I${CMAKE_SOURCE_DIR}/H -I${CMAKE_SOURCE_DIR}/H/generated -I${CMAKE_SOURCE_DIR}/include -I${CMAKE_SOURCE_DIR}/OPTYap -I${CMAKE_SOURCE_DIR}/os -I${CMAKE_SOURCE_DIR}/utf8proc -I.././.. -I${CMAKE_SOURCE_DIR}/CXX -I${CMAKE_SOURCE_DIR}/packages/python -outdir ${CMAKE_CURRENT_BINARY_DIR}/yap4py -I${GMP_INCLUDE_DIRS} -DX_API=""   -o ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.cxx -oh ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.hh ${SWIG_SOURCES}  
-     -I${CMAKE_SOURCE_DIR}/OPTYap -I${CMAKE_SOURCE_DIR}/os -I${CMAKE_SOURCE_DIR}/utf8proc -I.././.. -I${CMAKE_SOURCE_DIR}/CXX -I${CMAKE_SOURCE_DIR}/packages/python
-      -outdir ${CMAKE_CURRENT_BINARY_DIR}/yap4py -I${GMP_INCLUDE_DIRS} -DX_API=""   -o ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.cxx -oh ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.hh ${SWIG_SOURCES}  
      WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
-    DEPENDS  ${SWIG_SOURCES} yap4py/yapi.cpp
+    DEPENDS  ${SWIG_SOURCES} YAP++
-  )
-
-
-add_custom_target( YAP4PY ALL
-  DEPENDS ${CMAKE_SOURCE_DIR}/CXX/yapi.cpp Py4YAP YAP++ yap4py/yapi.cpp  ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.cxx ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.hh 
   )
 
  
-add_custom_command( TARGET YAP4PY
+add_custom_target( YAP4PY ALL
-  PRE_BUILD
   COMMAND ${CMAKE_COMMAND} -E copy ${PYTHON_SOURCES}  ${CMAKE_CURRENT_BINARY_DIR}/yap4py
  COMMAND ${PYTHON_EXECUTABLE} setup.py sdist ${bdist}
   DEPENDS ${CMAKE_SOURCE_DIR}/CXX/yapi.cpp Py4YAP YAP++ yap4py/yapi.cpp YAP4PY_PY ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.cxx ${CMAKE_CURRENT_BINARY_DIR}/yap4py/yap_wrap.hh ${PYTHON_SOURCES} Py4YAP STARTUP libYap

pl/debug.yap

@@ -296,27 +296,10 @@ be lost.
   * @param _Mod_:_Goal_ is the goal to be examined.
   * @return `call(Goal)`
 */
-'$trace'(Mod:G) :-
+%%! The first case matches system_predicates or zip
-    '$creep_is_off'(Mod:G,_GN0),
-     !,
-    gated_call(
-	true,
-	Mod:G,
-	E,
-	'$reenter_debugger'(E)
-    ).
 '$trace'(Mod:G) :-
     '$$save_by'(CP),
-    '$trace_query'(G, Mod, CP, G, EG),
+    '$trace_query'(G, Mod, CP, _G).
-    gated_call(
-	'$debugger_io',
-	( '$enter_debugging'(G,Mod), EG ),
-	E,
-	'$continue_debugging'(E)
-    ).
-
-
-
 
 
 '$trace'(Mod:G, A1) :-
@@ -408,100 +391,133 @@ be lost.
 
 
 '$trace_meta_call'( G, M, CP ) :-
-    '$trace_query'(G, M, CP, G, EG ),
+    '$trace_query'(G, M, CP, _G ).
-    call(EG).
 
 %% @pred '$trace_query'( +G, +M, +CP, +Expanded)
 %
 % debug a complex query
 %
-'$trace_query'(V, M, _CP, _, call(M:V)) :-
+'$trace_query'(V, M, _CP, _) :-
-    var(V), !.
+    var(V), !, call(M:V).
-'$trace_query'(!, _, CP, _, '$$cut_by'(CP)) :-
+'$trace_query'(!, _, CP, _) :-
-    !.
+    !, '$$cut_by'(CP).
-'$trace_query'('$cut_by'(M), _, _, _, '$$cut_by'(M)) :-
+'$trace_query'('$cut_by'(M), _, _, _) :-
-    !.
+    !, '$$cut_by'(M).
-'$trace_query'('$$cut_by'(M), _, _, _, '$$cut_by'(M)) :-
+'$trace_query'('$$cut_by'(M), _, _, _) :-
-    !.
+    !, '$$cut_by'(M).
-'$trace_query'(true, _, _, _, true) :- !.
+'$trace_query'(M:G, _, CP,S) :-
-'$trace_query'(fail, _, _, _, '$trace'(fail)) :- !.
-'$trace_query'(M:G, _, CP,S, Expanded) :-
     !,
     '$yap_strip_module'(M:G, M0, G0),
-    '$trace_query'(G0, M0, CP,S, Expanded ).
+    '$trace_query'(G0, M0, CP,S ).
-'$trace_query'((A,B), M, CP, S, (EA,EB)) :- !,
+'$trace_query'((A,B), M, CP, S) :- !,
-    '$trace_query'(A, M, CP, S, EA),
+    '$trace_query'(A, M, CP, S),
-    '$trace_query'(B, M, CP, S, EB).
+    '$trace_query'(B, M, CP, S).
-'$trace_query'((A->B), M, CP, S, (EA->EB)) :- !,
+'$trace_query'((A->B), M, CP, S) :- !,
-    '$trace_query'(A, M, CP, S, EA),
+    '$trace_query'(A, M, CP, S) ->
-    '$trace_query'(B, M, CP, S, EB).
+    '$trace_query'(B, M, CP, S).
-'$trace_query'((A;B), M, CP, S, (EA;EB)) :- !,
+'$trace_query'((A;B), M, CP, S) :- !,
-	'$trace_query'(A, M, CP, S, EA),
+	'$trace_query'(A, M, CP, S);
-	'$trace_query'(B, M, CP, S, EB).
+	'$trace_query'(B, M, CP, S).
-'$trace_query'((A|B), M, CP, S, (EA|EB)) :- !,
+'$trace_query'((A|B), M, CP, S) :- !,
-	'$trace_query'(A, M, CP, S, EA),
+	'$trace_query'(A, M, CP, S);
-	'$trace_query'(B, M, CP, S, EB).
+	'$trace_query'(B, M, CP, S).
-'$trace_query'((\+ A), M, CP, S, (\+ EA)) :- !,
+'$trace_query'((\+ A), M, CP, S) :- !,
-	'$trace_query'(A, M, CP, S, EA).
+	'$trace_query'(A, M, CP, S).
-'$trace_query'(G, M, _CP, _, (
+'$trace_query'(G, M,_CP,S) :-
+        '$is_metapredicate'(G, prolog),
+        !,
+        '$debugger_expand_meta_call'(M:G, [], G1),
+	strip_module(M:G1, MF, NG),
+        % spy a literal
+	'$id_goal'(L),
+        catch(
+            '$trace_goal'(NG, MF, L, S),
+            E,
+            '$TraceError'(E, G, M, L, S)
+            ).
+'$trace_query'(G, M, _CP, H) :-
         % spy a literal
 	'$id_goal'(L),
         catch(
             '$trace_goal'(G, M, L, H),
             E,
             '$TraceError'(E, G, M, L, H)
-            ))).
+            ).
+
 
 %% @pred $trace_goal( +Goal, +Module, +CallId, +CallInfo)
 %%
 %% Actually debugs a
 %% goal!
+'$trace_goal'(G,M, _GoalNumber, _H) :-
+    (
+	'$is_private'(G, M)
+    ;
+    current_prolog_flag(debug,false)
+    ),
+    !,
+     gated_call(
+	 '$start_user_code',
+	 % try creeping
+	 '$execute_nonstop'(G,M),
+	 Port,
+	 '$reenter_debugger'(Port)
+     ).
+'$trace_goal'(G,M, GoalNumber, H) :-
+    '$enter_trace'(GoalNumber, G, M, H),
+    '$creep_is_off'(M:G, GoalNumber),
+    !,
+     gated_call(
+	 '$start_user_code',
+	 % try creeping
+	 '$execute_nonstop'(G,M),
+	 Port,
+	 '$trace_port_'( Port, GoalNumber, G, M, H)
+     ).
 '$trace_goal'(G,M, GoalNumber, H) :-
     '$is_source'(G,M),
-    '$current_choice_point'(CP),
     !,
-    '$enter_trace'(GoalNumber, G, M, H),
+    '$current_choice_point'(CP),
+    %clause generator: it controls fail, redo
     gated_call(
 	true,
-	( '$enter_debugging'(G,M,GoalNumber)
+	clause(M:G, B),
-	->
+	Port0,
-	% source mode
+ 	'$trace_port'(pred,Port0, GoalNumber, G, M, H)
-	clause(M:G, B), '$trace_query'(B,M,CP,B,H)
+    ),
-	;
+    gated_call(
-	'$execute_nonstop'(G,M)
+	true,% source mode
-	),
+	    '$trace'(B,M,CP,H),
 	Port,
 	(
-	    '$reenter_debugging'(Port,G,M,GoalNumber),
+	    '$trace_port'(clause,Port, GoalNumber, G, M, H)
-	    '$trace_port'(Port, GoalNumber, G, M, true, H)
 	)
     ).
+'$trace_goal'(G,M, GoalNumber, H) :-
+    !,
+    '$current_choice_point'(CP),
+    %clause generator: it controls fail, redo
+    gated_call(
+	true,
+	'$static_clause'(G,M,_,Ref),
+	Port0,
+ 	'$trace_port'(pred,Port0, GoalNumber, G, M, H)
+    ),
+    gated_call(
+	'$start_user_code',
+	% source mode
+	'$creep_clause'(G,M,Ref,CP),
+	Port,
+	    '$trace_port'(clause, Port, GoalNumber, G, M, H)
+    ).
 '$trace_goal'(G, M, GoalNumber, H) :-
-        '$is_metapredicate'(G, prolog),
-        !,
-        '$debugger_expand_meta_call'(M:G, [], G1),
-	strip_module(G1, MF, NG),
-	'$trace_goal__'(NG,MF, GoalNumber, H).
-'$trace_goal'(G, M, GoalNumber, H) :-
-	'$trace_goal__'(G,M, GoalNumber, H).
-
-'$trace_goal__'(G,M, _GoalNumber, _H) :-
     '$undefined'(G,M),
     !,
-    '$undefp'([M|G], _).    
+    '$undefp'([M|G], G1),
+    strip_module(G1, MF, NG),
+    '$trace_goal'(NG,MF, GoalNumber, H).
+    
 % system_
-'$trace_goal__'(G,M, GoalNumber, H) :-
-    '$enter_trace'(GoalNumber, G, M, H),
-     gated_call(
-         true,
-	 (
-	     % try creeping
-	     ( '$enter_debugging'(G,M,GoalNumber) -> '$creep' ; true ),
-	     '$execute_nonstop'(G,M)
-	     ),
-	 Port,
-	 '$trace_port'(Port, GoalNumber, G, M, true, H)
-     ).
 
 
 /**
@@ -515,22 +531,12 @@ be lost.
  *
  */
 '$enter_trace'(L, G, Module, Info) :-
-        /* get goal no.	*/
+    '$id_goal'(L),        /* get goal no.	*/
-        ( var(L) ->
-        '__NB_getval__'('$spy_gn',L,fail),
-        /* bump it			*/
-        L1 is L+1,
-        /* and save it globaly		*/
-        '__NB_setval__'('$spy_gn',L1)
-        ;
-        true
-        ),
         /* get goal list		*/
         '__NB_getval__'('$spy_glist',History,History=[]),
 	H  = [Info|History],
 	Info = info(L,Module,G,_Retry,_Det,_HasFoundAnswers),
-	b_setval('$spy_glist',H),
+	b_setval('$spy_glist',H),	/* and update it		*/
-	/* and update it		*/
 	'$port'(call,G,Module,L,deterministic, Info).
 
 '$id_goal'(L) :-
@@ -556,58 +562,44 @@ be lost.
  * @parameter _Info_ describes the goal
  *
  */
-'$trace_go'(GoalNumber, G, M, Info) :-
+'$trace_port'(_, _, _GoalNumber, _G, _Module, _Info) :-
-    X=marker(_,M,G),
+    '$stop_creeping'(_),
-    '$$save_by'(CP),
+    fail.
-    clause(M:G, Cl, _),
-    '$retry_clause'(GoalNumber, G, M, Info, X),
-    '$trace_query'(Cl, M, CP, Cl, ECl),
-    '$execute0'(ECl,M).
 
-'$creep_step'(GoalNumber, G, M, Info) :-
+'$trace_port'(pred, fail, GoalNumber, G, Module, Info) :-
-    X=marker(_,M,G),
+    !,
-    '$$save_by'(CP),
+    '$trace_port_'(fail, GoalNumber, G, Module, Info).
-    '$static_clause'(G,M,_,Ref),
+'$trace_port'(pred, call, GoalNumber, G, Module, Info) :-
-    '$retry_clause'(GoalNumber, G, M, Info, X),
+    !,
-    '$creep',
+    '$trace_port_'(call, GoalNumber, G, Module, Info).
-    '$execute_clause'(G,M,Ref,CP).
+'$trace_port'(pred, redo, GoalNumber, G, Module, Info) :-
-
-'$retry_clause'(_GoalNumber, _G, _M, _Info, MarkerV) :-
-    arg(1, MarkerV, V),
-    var(V),
     !,
-    nb_setarg(1,MarkerV, visited).
-'$retry_clause'(GoalNumber, G, Module, Info, _X) :-
     '$trace_port_'(redo, GoalNumber, G, Module, Info).
+'$trace_port'(pred, _Port, _GoalNumber, _G, _Module, _Info).
+ 
 
-'$trace_port'(Port, GoalNumber, G, Module, _CalledFromDebugger, Info) :-
+'$trace_port'(clause, call, _GoalNumber, _G, _Module, _Info).
-    '$trace_off',
+'$trace_port'(clause, fail, _GoalNumber, _G, _Module, _Info) :-
+    fail.
+'$trace_port'(clause, Port, GoalNumber, G, Module, Info) :-
     !,
-    '$trace_port_'(Port, GoalNumber, G, Module, Info),
+    '$trace_port_'(Port, GoalNumber, G, Module, Info).
-    '$continue_debugging'(Port).
-'$trace_port'(Port, _GoalNumber, _G, _Module, _CalledFromDebugger, _Info) :-
-    '$continue_debugging'(Port).
 
 '$trace_port_'(call, GoalNumber, G, Module, Info) :-
     '$port'(call,G,Module,GoalNumber,deterministic, Info).
 '$trace_port_'(exit, GoalNumber, G, Module, Info) :-
-    nb_setarg(6, Info, true),
     '$port'(exit,G,Module,GoalNumber,deterministic, Info).
 '$trace_port_'(answer, GoalNumber, G, Module, Info) :-
     '$port'(exit,G,Module,GoalNumber,nondeterministic, Info).
 '$trace_port_'(redo, GoalNumber, G, Module, Info) :-
-    '$stop_creeping'(_ ),
     '$port'(redo,G,Module,GoalNumber,nondeterministic, Info). /* inform user_error	*/
 '$trace_port_'(fail, GoalNumber, G, Module, Info) :-
-    '$stop_creeping'(_ ),
     '$port'(fail,G,Module,GoalNumber,deterministic, Info). /* inform user_error		*/
 '$trace_port_'(! ,_GoalNumber,_G,_Module,_Imfo) :- /* inform user_error		*/
     !.
 '$trace_port_'(exception(E), GoalNumber, G, Module, Info) :-
-        '$stop_creeping'(_ ),
     '$TraceError'(E, GoalNumber, G, Module, Info).
 '$trace_port_'(external_exception(E), GoalNumber, G, Module, Info) :-
-    '$stop_creeping'(_ ),
     '$TraceError'(E, GoalNumber, G, Module, Info).
 
 
@@ -731,7 +723,7 @@ be lost.
     '__NB_getval__'('$trace',Trace,fail),
     '__NB_setval__'('$debug_status', state(creep, 0, stop, Trace)).
 '$action'(!,_,_,_,_,_) :- !,			% ! 'g		execute
-	read(debugger_input, G),
+    read(debugger_input, G),
 	% don't allow yourself to be caught by creep.
 	ignore( G ),
 	skip( debugger_input, 10),                        % '
@@ -753,7 +745,6 @@ be lost.
 	fail.
 '$action'(a,_,_,_,_,_) :- !,		% 'a		abort
 	skip( debugger_input, 10),
-    '$stop_creeping'(_),
     nodebug,
 	abort.
 '$action'(b,_,_,_,_,_) :- !,			% 'b		break

pl/signals.yap

@@ -295,18 +295,18 @@ read_sig.
 				% %
 				% make thes predicates non-traceable. %
 
-:- '$set_no_trace'(current_choicepoint(_DCP), yap_hacks).
+:- '$set_private'(current_choicepoint(_DCP), yap_hacks).
-:- '$set_no_trace'('$current_choice_point'(_DCP), _).
+:- '$set_private'('$current_choice_point'(_DCP), _).
-:- '$set_no_trace'('$$cut_by'(_DCP), prolog).
+:- '$set_private'('$$cut_by'(_DCP), prolog).
-:- '$set_no_trace'(true, yap_hacks).
+:- '$set_private'(true, yap_hacks).
-:- '$set_no_trace'(true, prolog).
+:- '$set_private'(true, prolog).
-:- '$set_no_trace'('$call'(_,_,_,_), prolog).
+:- '$set_private'('$call'(_,_,_,_), prolog).
-:- '$set_no_trace'('$execute_nonstop'(_,_), prolog).
+:- '$set_private'('$execute_nonstop'(_,_), prolog).
-:- '$set_no_trace'('$execute_clause'(_,_,_,_), prolog).
+:- '$set_private'('$execute_clause'(_,_,_,_), prolog).
-:- '$set_no_trace'('$restore_regs'(_,_), prolog).
+:- '$set_private'('$restore_regs'(_,_), prolog).
-:- '$set_no_trace'('$undefp'(_,_), prolog).
+:- '$set_private'('$undefp'(_,_), prolog).
-:- '$set_no_trace'('$Error'(_), prolog).
+:- '$set_private'('$Error'(_), prolog).
-:- '$set_no_trace'('$LoopError'(_,_), prolog).
+:- '$set_private'('$LoopError'(_,_), prolog).
-:- '$set_no_trace'('$TraceError'(_,_,_,_,_), prolog).
+:- '$set_private'('$TraceError'(_,_,_,_,_), prolog).
 
 %%! @}

pl/spy.yap

@@ -200,13 +200,15 @@ nospyall.
 debug :-
 	 '$init_debugger',
 	 ( '__NB_getval__'('$spy_gn',_, fail) -> true ; '__NB_setval__'('$spy_gn',1) ),
-	 '$start_debugging'(on),
+	 set_prolog_flag(debug,true),
+	 '$start_user_code',
 	 print_message(informational,debug(debug)).
 
-'$start_debugging'(_Mode) :-
+'$start_user_code' :-
-    '__NB_setval__'(debug, false),
+    yap_flag(debug, Can),
+    '__NB_setval__'(debug, Can),
     '__NB_getval__'('$trace',Trace, fail),
-    ( Trace == on -> Creep = crep; Creep = zip ),
+    ( Trace == on -> Creep = creep; Creep = zip ),
     '__NB_setval__'('$debug_state',state(Creep,0,stop,Trace) ).
 
 nodebug :-
@@ -228,13 +230,10 @@ Switches on the debugger and enters tracing mode.
 
 */
 trace :-
-    '$init_debugger',
-     fail.
-trace :-
-    '__NB_setval__'('$trace',on),
-    '$start_debugging'(on),
     print_message(informational,debug(trace)),
-    '$creep'.
+    set_prolog_flag(debug,true),
+    '__NB_setval__'('$trace',on),
+    '$init_debugger'.
 
 /** @pred notrace
 
@@ -392,16 +391,18 @@ notrace(G) :-
     '$enable_debugging'.
 
 '$init_debugger' :- 
-	'$init_debugger_trace',
+    '$debugger_io',
+    '$init_debugger_trace',
 	'__NB_setval__'('$if_skip_mode',no_skip),
 	'__NB_setval__'('$spy_glist',[]),
 	'__NB_setval__'('$spy_gn',1).
  
 '$init_debugger_trace' :-
 	'__NB_getval__'('$trace',on,fail),
-	!, 
+	!,
-		nb_setval('$debug_status', state(creep, 0, stop, on)).  
+	nb_setval('$debug_status', state(creep, 0, stop, on)).  
 '$init_debugger_trace' :-
+	'__NB_setval__'('$trace',off),
 	nb_setval('$debug_status', state(zip, 0, stop, off)). 
 
 %% @pred $enter_debugging(G,Mod,CP,G0,NG)
@@ -409,14 +410,27 @@ notrace(G) :-
 %% Internal predicate called by top-level;
 %% enable creeping on a goal by just switching execution to debugger.
 %%
-'$enter_debugging'(G,Mod,CP,G0,NG) :-
+'$enter_debugging'(G,Mod,_CP,_G0,_NG) :-
     '$creepcalls'(G,Mod),
-    !,
+    !.
-    '$trace_query'(G,Mod,CP,G0,NG).
 '$enter_debugging'(G,_Mod,_CP,_G0,G).
 
 '$enter_debugging'(G,Mod,GN) :-
-    çurrent_prolog_flag( debug, Deb ),
+    current_prolog_flag( debug, Deb ),
+    '__NB_set_value__'( debug, Deb ),
+    ( Deb = false
+    ->
+    true
+    ;
+    '$creep_is_on_at_entry'(G,Mod,GN)
+    ->
+    '$creep'
+    ;
+    true
+    ).
+
+'$exit_debugger'(Mod:G, GN) :-
+    current_prolog_flag( debug, Deb ),
     '__NB_set_value__'( debug, Deb ),
     ( Deb = false
     ->
@@ -431,7 +445,7 @@ notrace(G) :-
 
 %% we're coming back from external code to a debugger call.
 %%
-'$reenter_debugger'(retry) :-
+'$reenter_debugger'(fail) :-
     '$re_enter_creep_mode'.
 '$reenter_debugger'(_) :-
     '__NB_setval__'(debug, false).
@@ -442,10 +456,15 @@ notrace(G) :-
     '$re_enter_creep_mode'.
 '$continue_debugging'(answer) :-
     !,
-    '$re_enter_creep_mode'.
+    '$re_enter_creep_mode'.			   
 '$continue_debugging'(fail) :-
     !,
     '$re_enter_creep_mode',
+    fail.
+'$continue_debugging'(redo) :-
+    !,
+    '$re_enter_creep_mode',
+    fail.
 '$continue_debugging'(_).
 
 '$enable_debugging' :-
@@ -458,33 +477,37 @@ notrace(G) :-
 %% enable creeping on the next goal.
 %%
 '$re_enter_creep_mode' :-
-    !,
+    current_prolog_flag( debug, Deb ),
-    '$creep'.
+    '__NB_setval__'( debug, Deb ).
-'$re_enter_creep_mode'.
 
-'$creep_is_off'(Module:G, GN0) :-
+
-    '__NB_getval__'('$debug_status',state(zip, GN, Spy,_), fail),
+'$creep_is_off'(Module:G, GoalNo) :-
-    (
+     (
-	
+	 current_prolog_flag( debug, false )
+     -> true
+    ;
+	 '$system_predicate'(G,Module)
+     -> true
+    ;
+	 '$is_private'(G,Module)
+     -> true
+    ;
+    '__NB_getval__'('$debug_status',state(zip, GN, Spy,_), fail)
+    ->
+    true
+    ;
     '$pred_being_spied'(G,Module)
     ->
     Spy == ignore
     ;
-    var(GN0)
+    var(GN)
     ->
-    true
+    false
     ;
-    GN > GN0
+    GN > GoalNo
-   ). 
+     ).
-
+'$creep_is_on_at_entry'(G,M,_GoalNo) :-
-%%
+    \+ '$system_predicate'(G,M),
-%
-'$creep_is_on' :-
-    '__NB_getval__'('$debug_status',state(Step, _GN, _Spy,_), fail),
-    Step \= zip.
-
-'$creep_is_on_at_entry'(G,M,GoalNo) :-
-	\+ '$system_predicate'(G,M),
     '__NB_getval__'('$debug_status',state(Step, _GN, Spy,_), fail),
     (
 	Step \= zip
@@ -496,7 +519,7 @@ notrace(G) :-
    
 '$trace_on' :-
     '__NB_getval__'('$debug_status', state(_Creep, GN, Spy,Trace), fail),
-    nb_getval('$trace',on),
+    nb_setval('$trace',on),
     nb_setval('$debug_status', state(creep, GN, Spy, Trace)).
 
 '$trace_off' :-

pl/top.yap

@@ -93,16 +93,6 @@ live :-
     ;   '$halt'(0)
     ).
 
-'$init_debug' :-
-    nb_setval('$spy_gn', 1),
-				 % stop at spy-points if debugging is on.
-    nb_setval('$debug_run', off),
-    nb_setval('$debug_jump', off),
-    '__NB_getval__'('$trace', Trace, fail),
-    (   Trace==on
-    ->  nb_setval('$debug_status', state(creep, 0, stop, on))
-    ;   nb_setval('$debug_status', state(zip, 0, stop, off))
-    ).
 
 '$erase_sets' :-
     eraseall($),
@@ -587,21 +577,10 @@ write_query_answer( Bindings ) :-
 	'$call'(G, CP, G, M).
 
 '$user_call'(G, CP, G0, M) :-
-        gated_call(
+    '$trace_query'(G, M, CP, G0).    
-	    '$enable_debugging',
-            '$call'(G, CP, G0, M),
-	    Port,
-	'$reenter_debugger'(Port)
-       ).
-    
 
 '$user_call'(G, M) :-
-        gated_call(
+	'$trace'(M:G).
-                '$enable_debugging',
-                M:G,
-	         Port,
-			'$reenter_debugger'(Port)
-       ).
 
 '$cut_by'(CP) :- '$$cut_by'(CP).