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yap-6.3/C/exec.c

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/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: exec.c *
* Last rev: 8/2/88 *
* mods: *
* comments: Execute Prolog code *
* *
*************************************************************************/
#ifdef SCCS
static char SccsId[] = "@(#)cdmgr.c 1.1 05/02/98";
#endif
#include "absmi.h"
#include "yapio.h"
STATIC_PROTO(Int CallProlog, (PredEntry *, unsigned int, Int));
STATIC_PROTO(Int p_save_cp, (void));
STATIC_PROTO(Int p_execute, (void));
STATIC_PROTO(Int p_execute0, (void));
STATIC_PROTO(Int p_at_execute, (void));
static Int
FastCallProlog(PredEntry *pen) {
#ifdef DEPTH_LIMIT
if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is prolog */
if (pen->ModuleOfPred) {
if (DEPTH == MkIntTerm(0))
return(FALSE);
else DEPTH = RESET_DEPTH();
}
} else if (pen->ModuleOfPred)
DEPTH -= MkIntConstant(2);
#endif /* DEPTH_LIMIT */
#ifdef LOW_LEVEL_TRACER
if (do_low_level_trace)
low_level_trace(enter_pred,pen,XREGS+1);
#endif /* LOW_LEVEL_TRACE */
if (pen->PredFlags & ProfiledPredFlag)
pen->StatisticsForPred.NOfEntries++;
CP = P;
P = (yamop *)(pen->CodeOfPred);
WRITE_UNLOCK(pen->PRWLock);
ENV = YENV;
YENV = ASP;
YENV[E_CB] = (CELL) B;
return (Unsigned(&(pen->StateOfPred)));
}
static Int
CallProlog(PredEntry *pen, unsigned int arity, Int position)
{
CELL flags;
WRITE_LOCK(pen->PRWLock);
flags = pen->PredFlags;
if ((flags & (CompiledPredFlag | DynamicPredFlag)) ||
pen->OpcodeOfPred == UNDEF_OPCODE) {
if (position == -1 ||
pen->OpcodeOfPred == UNDEF_OPCODE) {
return(FastCallProlog(pen));
} else {
CODEADDR q;
#ifdef DEPTH_LIMIT
if (DEPTH <= MkIntTerm(1)) {/* I assume Module==0 is prolog */
if (pen->ModuleOfPred) {
if (DEPTH == MkIntTerm(0))
return(FALSE);
else DEPTH = RESET_DEPTH();
}
} else if (pen->ModuleOfPred)
DEPTH -= MkIntConstant(2);
#endif /* DEPTH_LIMIT */
#ifdef LOW_LEVEL_TRACER
if (do_low_level_trace)
low_level_trace(enter_pred,pen,XREGS+1);
#endif /* LOW_LEVEL_TRACE */
ENV = YENV;
YENV = ASP;
YENV[E_CB] = (CELL)(B->cp_b);
CP = P;
q = pen->FirstClause;
if (pen->PredFlags & ProfiledPredFlag) {
LOCK(pen->StatisticsForPred.lock);
if (position == 1)
pen->StatisticsForPred.NOfEntries++;
else
pen->StatisticsForPred.NOfRetries++;
UNLOCK(pen->StatisticsForPred.lock);
}
if (flags & DynamicPredFlag) {
CLAUSECODE->arity = pen->ArityOfPE;
CLAUSECODE->func = pen->FunctorOfPred;
while (position > 1) {
while (ClauseCodeToClause(q)->ClFlags & ErasedMask)
q = NextClause(q);
position--;
q = NextClause(q);
}
while (ClauseCodeToClause(q)->ClFlags & ErasedMask)
q = NextClause(q);
#if defined(YAPOR) || defined(THREADS)
{
Clause *cl = ClauseCodeToClause(q);
LOCK(cl->ClLock);
TRAIL_REF(&(cl->ClFlags));
INC_DBREF_COUNT(cl);
UNLOCK(cl->ClLock);
}
#else
if (!(ClauseCodeToClause(q)->ClFlags & InUseMask)) {
OPREG *opp = &(ClauseCodeToClause(q)->ClFlags);
TRAIL_REF(opp);
*opp |= InUseMask;
}
#endif
CLAUSECODE->clause = (CODEADDR)NEXTOP((yamop *)(q),ld);
P = (yamop *)CLAUSECODE->clause;
WRITE_UNLOCK(pen->PRWLock);
return((CELL)(&(CLAUSECODE->clause)));
} else {
for (; position > 1; position--)
q = NextClause(q);
P = NEXTOP((yamop *)(q),ld);
WRITE_UNLOCK(pen->PRWLock);
return (Unsigned(&(pen->StateOfPred)));
}
}
}
if (flags & UserCPredFlag) {
Int(*p) (void) = (Int(*) (void)) pen->CodeOfPred;
Int out;
WRITE_UNLOCK(pen->PRWLock);
save_machine_regs();
out = YapExecute(p);
restore_machine_regs();
return(out);
}
if (flags & CPredFlag) {
Int(*p) (void) = (Int(*) (void)) pen->CodeOfPred;
WRITE_UNLOCK(pen->PRWLock);
return ((*p) ());
} else if (flags & BasicPredFlag) {
if (pen->OpcodeOfPred != UNDEF_OPCODE) {
Int(*p) (void) = (Int(*) (void)) pen->CodeOfPred;
WRITE_UNLOCK(pen->PRWLock);
return (((*p) ()) != FALSE);
}
}
return (FALSE);
}
static Term
current_cp_as_integer(void)
{
return(MkIntTerm(LCL0-(CELL *)B));
}
static Int
p_save_cp(void)
{
Term t = Deref(ARG1);
Term td;
#if SHADOW_HB
register CELL *HBREG = HB;
#endif
if (!IsVarTerm(t)) return(FALSE);
td = current_cp_as_integer();
BIND((CELL *)t,td,bind_save_cp);
#ifdef COROUTINING
DO_TRAIL(CellPtr(t), td);
if (CellPtr(t) < H0) WakeUp((CELL *)t);
bind_save_cp:
#endif
return(TRUE);
}
inline static int
SpecialCallFunctor(Functor f) {
return(f == FunctorComma || f == FunctorOr || f == FunctorArrow ||
f == FunctorVBar || f == FunctorNot || f == FunctorAltNot);
}
inline static Int
CallMetaCall(void) {
ARG2 = current_cp_as_integer(); /* p_save_cp */
ARG3 = TermNil;
WRITE_LOCK(PredMetaCall->PRWLock);
return (FastCallProlog(PredMetaCall));
}
static Int
p_execute(void)
{ /* '$execute'(Goal) */
Term t = Deref(ARG1);
unsigned int arity;
Prop pe;
Atom a;
restart_exec:
if (yap_flags[SPY_CREEP_FLAG]) {
a = NameOfFunctor(FunctorSpiedMetaCall);
return (CallProlog(RepPredProp(PredProp(a,1)), 1, (Int) (-1)));
}
if (PredGoalExpansion->OpcodeOfPred != UNDEF_OPCODE) {
return(CallMetaCall());
} else if (IsVarTerm(t)) {
if (yap_flags[LANGUAGE_MODE_FLAG] == 1) {
return(CallMetaCall());
} else {
Error(INSTANTIATION_ERROR,t,"call/1");
return(FALSE);
}
} else if (IsApplTerm(t)) {
register Functor f = FunctorOfTerm(t);
register unsigned int i;
register CELL *pt;
if (IsExtensionFunctor(f)) {
if (yap_flags[LANGUAGE_MODE_FLAG] == 1) {
return(CallMetaCall());
} else {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
}
if (SpecialCallFunctor(f)) {
return(CallMetaCall());
} else if (f == FunctorModule) {
Term mod = ArgOfTerm(1, t);
if (mod == ModuleName[CurrentModule]) {
/* we can skip this operation */
/* should catch most cases */
t = ArgOfTerm(2, t);
goto restart_exec;
} else {
/* I can't do better because I don't have a way of restoring the module */
return(CallMetaCall());
}
} else {
PredEntry *pen;
arity = ArityOfFunctor(f);
a = NameOfFunctor(f);
if (CurrentModule)
pe = PredProp(a, arity);
else {
pe = GetPredProp(a, arity);
if (pe == NIL) {
return(CallMetaCall());
}
}
pen = RepPredProp(pe);
/* You thought we would be over by now */
/* but no meta calls require special preprocessing */
if (pen->PredFlags & MetaPredFlag) {
return(CallMetaCall());
}
/* now let us do what we wanted to do from the beginning !! */
/* I cannot use the standard macro here because
otherwise I would dereference the argument and
might skip a svar */
pt = RepAppl(t)+1;
for (i = 1; i <= arity; ++i) {
#if SBA
Term d0 = *pt++;
if (d0 == 0)
XREGS[i] = (CELL)(pt-1);
else
XREGS[i] = d0;
#else
XREGS[i] = *pt++;
#endif
}
return (CallProlog(pen, arity, (Int) (-1)));
}
} else if (IsAtomOrIntTerm(t)) {
if (IsIntTerm(t)) {
if (yap_flags[LANGUAGE_MODE_FLAG] == 1) {
return (CallMetaCall());
} else {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
}
a = AtomOfTerm(t);
if (a == AtomTrue || a == AtomOtherwise || a == AtomCut)
return(TRUE);
else if (a == AtomFail || a == AtomFalse)
return(FALSE);
else
arity = 0;
/* call may not define new system predicates!! */
if (CurrentModule)
pe = PredProp(a, arity);
else {
pe = GetPredProp(a, arity);
if (pe == NIL) {
ARG1 = t;
return(CallMetaCall());
}
}
return (CallProlog(RepPredProp(pe), arity, (Int) (-1)));
} else {
/* Is Pair Term */
return(CallMetaCall());
}
}
inline static Int
CallMetaCallWithin(void)
{
WRITE_LOCK(PredMetaCall->PRWLock);
return (FastCallProlog(PredMetaCall));
}
/* '$execute_within'(Goal,CutPt,OrigGoal) */
static Int
p_execute_within(void)
{
Term t = Deref(ARG1);
unsigned int arity;
Prop pe;
Atom a;
restart_exec:
if (yap_flags[SPY_CREEP_FLAG]) {
a = NameOfFunctor(FunctorSpiedMetaCall);
return (CallProlog(RepPredProp(PredProp(a,1)), 1, (Int) (-1)));
}
if (PredGoalExpansion->OpcodeOfPred != UNDEF_OPCODE) {
return(CallMetaCallWithin());
} else if (IsVarTerm(t)) {
if (yap_flags[LANGUAGE_MODE_FLAG] == 1) {
return(CallMetaCallWithin());
} else {
Error(INSTANTIATION_ERROR,t,"call/1");
return(FALSE);
}
} else if (IsApplTerm(t)) {
register Functor f = FunctorOfTerm(t);
register unsigned int i;
register CELL *pt;
if (IsExtensionFunctor(f)) {
if (yap_flags[LANGUAGE_MODE_FLAG] == 1) {
return(CallMetaCallWithin());
} else {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
}
if (SpecialCallFunctor(f)) {
return(CallMetaCallWithin());
} else if (f == FunctorModule) {
Term mod = ArgOfTerm(1, t);
if (mod == ModuleName[CurrentModule]) {
/* we can skip this operation */
/* should catch most cases */
t = ArgOfTerm(2, t);
goto restart_exec;
} else {
/* I can't do better because I don't have a way of restoring the module */
return(CallMetaCallWithin());
}
} else {
PredEntry *pen;
arity = ArityOfFunctor(f);
a = NameOfFunctor(f);
if (CurrentModule)
pe = PredProp(a, arity);
else {
pe = GetPredProp(a, arity);
if (pe == NIL) {
return(CallMetaCallWithin());
}
}
pen = RepPredProp(pe);
/* You thought we would be over by now */
/* but no meta calls require special preprocessing */
if (pen->PredFlags & MetaPredFlag) {
return(CallMetaCallWithin());
}
/* now let us do what we wanted to do from the beginning !! */
/* I cannot use the standard macro here because
otherwise I would dereference the argument and
might skip a svar */
pt = RepAppl(t)+1;
for (i = 1; i <= arity; ++i) {
#if SBA
Term d0 = *pt++;
if (d0 == 0)
XREGS[i] = (CELL)(pt-1);
else
XREGS[i] = d0;
#else
XREGS[i] = *pt++;
#endif
}
return (CallProlog(pen, arity, (Int) (-1)));
}
} else if (IsAtomOrIntTerm(t)) {
if (IsIntTerm(t)) {
if (yap_flags[LANGUAGE_MODE_FLAG] == 1) {
return (CallMetaCallWithin());
} else {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
}
a = AtomOfTerm(t);
if (a == AtomTrue || a == AtomOtherwise || a == AtomCut)
return(TRUE);
else if (a == AtomFail || a == AtomFalse)
return(FALSE);
else
arity = 0;
/* call may not define new system predicates!! */
if (CurrentModule)
pe = PredProp(a, arity);
else {
pe = GetPredProp(a, arity);
if (pe == NIL) {
ARG1 = t;
return(CallMetaCallWithin());
}
}
return (CallProlog(RepPredProp(pe), arity, (Int) (-1)));
} else {
/* Is Pair Term */
return(CallMetaCallWithin());
}
}
static Int
p_execute0(void)
{ /* '$execute'(Goal) */
Term t = Deref(ARG1);
unsigned int arity;
Prop pe;
Atom a;
if (IsAtomTerm(t))
arity = 0, a = AtomOfTerm(t);
else if (IsApplTerm(t)) {
register Functor f = FunctorOfTerm(t);
register unsigned int i;
register CELL *pt;
if (IsExtensionFunctor(f))
return(FALSE);
arity = ArityOfFunctor(f);
a = NameOfFunctor(f);
/* I cannot use the standard macro here because
otherwise I would dereference the argument and
might skip a svar */
pt = RepAppl(t)+1;
for (i = 1; i <= arity; ++i)
#if SBA
{
Term d0 = *pt++;
if (d0 == 0)
XREGS[i] = (CELL)(pt-1);
else
XREGS[i] = d0;
}
#else
XREGS[i] = *pt++;
#endif
} else
return (FALSE); /* for the moment */
/* N = arity; */
/* call may not define new system predicates!! */
if (CurrentModule)
pe = PredProp(a, arity);
else {
pe = GetPredProp(a, arity);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), arity, (Int) (-1)));
}
static Int
p_execute_0(void)
{ /* '$execute_0'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
if (CurrentModule)
pe = PredProp(a, 0);
else {
pe = GetPredProp(a, 0);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 0, (Int) (-1)));
}
static Int
p_execute_1(void)
{ /* '$execute_0'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
if (CurrentModule)
pe = PredProp(a, 1);
else {
pe = GetPredProp(a, 1);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 1, (Int) (-1)));
}
static Int
p_execute_2(void)
{ /* '$execute_2'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
if (CurrentModule)
pe = PredProp(a, 2);
else {
pe = GetPredProp(a, 2);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 2, (Int) (-1)));
}
static Int
p_execute_3(void)
{ /* '$execute_3'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
if (CurrentModule)
pe = PredProp(a, 3);
else {
pe = GetPredProp(a, 3);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 3, (Int) (-1)));
}
static Int
p_execute_4(void)
{ /* '$execute_4'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
if (CurrentModule)
pe = PredProp(a, 4);
else {
pe = GetPredProp(a, 4);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 4, (Int) (-1)));
}
static Int
p_execute_5(void)
{ /* '$execute_5'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
ARG5 = ARG6;
if (CurrentModule)
pe = PredProp(a, 5);
else {
pe = GetPredProp(a, 5);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 5, (Int) (-1)));
}
static Int
p_execute_6(void)
{ /* '$execute_6'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
ARG5 = ARG6;
ARG6 = ARG7;
if (CurrentModule)
pe = PredProp(a, 6);
else {
pe = GetPredProp(a, 6);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 6, (Int) (-1)));
}
static Int
p_execute_7(void)
{ /* '$execute_7'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
ARG5 = ARG6;
ARG6 = ARG7;
ARG7 = ARG8;
if (CurrentModule)
pe = PredProp(a, 7);
else {
pe = GetPredProp(a, 7);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 7, (Int) (-1)));
}
static Int
p_execute_8(void)
{ /* '$execute_8'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
ARG5 = ARG6;
ARG6 = ARG7;
ARG7 = ARG8;
ARG8 = ARG9;
if (CurrentModule)
pe = PredProp(a, 8);
else {
pe = GetPredProp(a, 8);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 8, (Int) (-1)));
}
static Int
p_execute_9(void)
{ /* '$execute_9'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
ARG5 = ARG6;
ARG6 = ARG7;
ARG7 = ARG8;
ARG8 = ARG9;
ARG9 = ARG10;
if (CurrentModule)
pe = PredProp(a, 9);
else {
pe = GetPredProp(a, 9);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 9, (Int) (-1)));
}
static Int
p_execute_10(void)
{ /* '$execute_10'(Goal) */
Term t = Deref(ARG1);
Prop pe;
Atom a;
a = AtomOfTerm(t);
ARG1 = ARG2;
ARG2 = ARG3;
ARG3 = ARG4;
ARG4 = ARG5;
ARG5 = ARG6;
ARG6 = ARG7;
ARG7 = ARG8;
ARG8 = ARG9;
ARG9 = ARG10;
ARG10 = ARG11;
if (CurrentModule)
pe = PredProp(a, 10);
else {
pe = GetPredProp(a, 10);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), 10, (Int) (-1)));
}
#ifdef DEPTH_LIMIT
static Int
p_execute_depth_limit(void) {
Term d = Deref(ARG2);
if (IsVarTerm(d)) {
Error(INSTANTIATION_ERROR,d,"depth_bound_call/2");
} else if (!IsIntTerm(d)) {
Error(TYPE_ERROR_INTEGER, d, "depth_bound_call/2");
return(FALSE);
}
DEPTH = MkIntTerm(IntOfTerm(d)*2);
return(p_execute());
}
#endif
static Int
p_pred_goal_expansion_on(void) {
/* a goal needs expansion if we have goal_expansion defined or
if the goal is a meta-call */
return (PredGoalExpansion->OpcodeOfPred != UNDEF_OPCODE);
}
static Int
p_at_execute(void)
{ /* '$execute'(Goal,ClauseNumber) */
Term t = Deref(ARG1), t2 = Deref(ARG2);
unsigned int arity;
Prop pe;
Atom a;
if (IsAtomTerm(t))
arity = 0, a = AtomOfTerm(t);
else if (IsApplTerm(t)) {
register Functor f = FunctorOfTerm(t);
register unsigned int i;
register CELL *pt;
if (IsBlobFunctor(f))
return(FALSE);
arity = ArityOfFunctor(f);
a = NameOfFunctor(f);
/* I cannot use the standard macro here because
otherwise I would dereference the argument and
might skip a svar */
pt = RepAppl(t)+1;
for (i = 1; i <= arity; ++i)
#if SBA
{
Term d0 = *pt++;
if (d0 == 0)
XREGS[i] = (CELL)(pt-1);
else
XREGS[i] = d0;
}
#else
XREGS[i] = *pt++;
#endif
} else
return (FALSE); /* for the moment */
if (IsVarTerm(t2) || !IsIntTerm(t2))
return (FALSE);
/* N = arity; */
/* call may not define new system predicates!! */
if (CurrentModule) {
pe = PredProp(a, arity);
} else {
pe = GetPredProp(a, arity);
if (pe == NIL)
return(FALSE);
}
return (CallProlog(RepPredProp(pe), arity, IntOfTerm(t2)));
}
int
exec_absmi(int top)
{
int lval;
if (top && (lval = sigsetjmp (RestartEnv, 1)) != 0) {
if (lval == 1) { /* restart */
int depth;
/* otherwise, SetDBForThrow will fail entering critical mode */
PrologMode = UserMode;
/* find out where to cut to */
depth = SetDBForThrow(MkAtomTerm(LookupAtom("abort")));
if (depth == 0) {
Error(SYSTEM_ERROR, TermNil, "database entry for throw corrupted");
}
/* make the abstract machine jump where we want them to jump to */
#if defined(SBA) && defined(FROZEN_REGS)
B = (choiceptr)depth;
#else
B = (choiceptr)(LCL0-depth);
#endif
yap_flags[SPY_CREEP_FLAG] = 0;
CreepFlag = MinStackGap*(stack_overflows+1);
#if defined(__GNUC__) && defined(hppa)
/* siglongjmp resets the TR hardware register */
restore_TR();
#endif
P = (yamop *)FAILCODE;
}
if (lval == 2) { /* arithmetic exception */
/* must be done here, otherwise siglongjmp will clobber all the registers */
Error(YAP_matherror,TermNil,NULL);
/* reset the registers so that we don't have trash in abstract machine */
set_fpu_exceptions(yap_flags[LANGUAGE_MODE_FLAG] == 1);
P = (yamop *)FAILCODE;
}
if (lval == 3) { /* saved state */
return(FALSE);
}
}
PrologMode = UserMode;
return(absmi(0));
}
static int
do_goal(CODEADDR CodeAdr, int arity, CELL *pt, int args_to_save, int top)
{
choiceptr saved_b = B;
/* create an initial pseudo environment so that when garbage
collection is going up in the environment chain it doesn't get
confused */
YENV = ASP;
YENV[E_CP] = (CELL)P;
YENV[E_CB] = (CELL)B;
YENV[E_E] = (CELL)ENV;
#ifdef DEPTH_LIMIT
YENV[E_DEPTH] = DEPTH;
#endif
ENV = YENV;
ASP -= EnvSizeInCells;
/* and now create a pseudo choicepoint for much the same reasons */
CP = (yamop *) YESCODE;
/* this is an hack to save the arguments */
{
CELL *pt1 = XREGS+1+args_to_save;
while (pt1 > XREGS+1)
*--ASP = *--pt1;
}
*--ASP = MkIntTerm(args_to_save+1);
{
int i;
for (i = 0; i < arity; i++) {
XREGS[i+1] = *pt++;
}
}
B = (choiceptr)ASP;
B--;
#ifdef TABLING
if (top) {
DepFr_cons_cp(GLOBAL_root_dep_fr) = B;
}
#endif /* TABLING */
B->cp_h = H;
B->cp_tr = TR;
B->cp_cp = CP;
B->cp_ap = (yamop *) NOCODE;
B->cp_env = ENV;
B->cp_b = saved_b;
#ifdef DEPTH_LIMIT
B->cp_depth = DEPTH;
#endif /* DEPTH_LIMIT */
if (top) {
#if COROUTINING
RESET_VARIABLE((CELL *)GlobalBase);
DelayedVars = NewTimedVar((CELL)GlobalBase);
WokenGoals = NewTimedVar(TermNil);
MutableList = NewTimedVar(TermNil);
AttsMutableList = NewTimedVar(TermNil);
#endif
}
YENV = ASP = (CELL *)B;
HB = H;
YENV[E_CB] = Unsigned (B);
P = (yamop *) CodeAdr;
S = CellPtr (&(RepPredProp (PredProp (AtomCall, 1))->StateOfPred)); /* A1 mishaps */
TopB = B;
return(exec_absmi(top));
}
Int
execute_goal(Term t, int nargs)
{
Int out;
CODEADDR CodeAdr;
yamop *saved_p, *saved_cp;
int arity;
Atom a;
Prop pe;
PredEntry *ppe;
CELL *pt;
/* preserve the current restart environment */
/* visualc*/
/* just keep the difference because of possible garbage collections */
Int MyOldTopB = LCL0-(CELL *)TopB;
Int MyOldDelayedB = LCL0-(CELL *)DelayedB;
choiceptr OldTopB, OldDelayedB;
DelayedB = NULL;
/* forget we have a DelayedB to do, this is not a problem for the embedded computation to solve */
saved_p = P;
saved_cp = CP;
if (IsAtomTerm(t)) {
arity = 0;
a = AtomOfTerm(t);
pt = NULL;
} else if (IsApplTerm(t)) {
Functor f = FunctorOfTerm(t);
if (IsBlobFunctor(f)) {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
arity = ArityOfFunctor(f);
a = NameOfFunctor(f);
/* I cannot use the standard macro here because
otherwise I would dereference the argument and
might skip a svar */
pt = RepAppl(t)+1;
} else {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
pe = GetPredProp(a, arity);
ppe = RepPredProp(pe);
if (pe != NIL)
READ_LOCK(ppe->PRWLock);
if (pe == NIL ||
ppe->OpcodeOfPred == UNDEF_OPCODE ||
ppe->PredFlags & (UserCPredFlag|CPredFlag|BasicPredFlag) )
{
if (pe != NIL)
READ_UNLOCK(ppe->PRWLock);
return(CallMetaCall());
}
CodeAdr = RepPredProp (PredProp (a, arity))->CodeOfPred;
READ_UNLOCK(ppe->PRWLock);
out = do_goal(CodeAdr, arity, pt, nargs, FALSE);
if (out == 1) {
choiceptr old_B;
/* we succeeded, let's prune */
/* restore the old environment */
/* get to previous environment */
#ifdef YAPOR
CUT_prune_to((choiceptr)(ENV[E_CB]));
#else
B = (choiceptr)(ENV[E_CB]);
#endif /* YAPOR */
/* find out where we have the old arguments */
old_B = ((choiceptr)(ENV-(EnvSizeInCells+nargs+1)))-1;
{
int i;
for (i=1; i<= nargs; i++) {
#if MIN_ARRAY == 0
XREGS[i] = old_B->cp_args[i];
#else
XREGS[i] = old_B->cp_last.cp_args[i];
#endif
}
}
CP = saved_cp;
P = saved_p;
ASP = ENV;
ENV = (CELL *)(ENV[E_E]);
#ifdef DEPTH_LIMIT
DEPTH= ENV[E_DEPTH];
#endif
/* we have failed, and usually we would backtrack to this B,
trouble is, we may also have a delayed cut to do */
OldTopB = (choiceptr)(LCL0-MyOldTopB);
OldDelayedB = (choiceptr)(LCL0-MyOldDelayedB);
if (DelayedB != NULL) {
if (YOUNGER_CP(DelayedB,B)) {
/* we have a delayed cut to do */
if (YOUNGER_CP(OldTopB,DelayedB)) {
/* and this delayed cut is to before the c-code that actually called us */
B = OldTopB;
/* did we have a cut which was cutting more than our current cut? */
if (OldDelayedB != NULL && YOUNGER_CP(DelayedB,OldDelayedB))
DelayedB = OldDelayedB;
} else {
/* just cut back to where we should cut */
B = DelayedB;
DelayedB = OldDelayedB;
}
}
} else {
DelayedB = OldDelayedB;
}
TopB = OldTopB;
HB = B->cp_h;
YENV = ENV;
return(TRUE);
} else if (out == 0) {
ASP = B->cp_env;
{
int i;
for (i=1; i<= nargs; i++) {
#if MIN_ARRAY==0
XREGS[i] = B->cp_args[i];
#else
XREGS[i] = B->cp_last.cp_args[i];
#endif
}
}
P = saved_p;
CP = saved_cp;
H = B->cp_h;
#ifdef DEPTH_LIMIT
DEPTH= B->cp_depth;
#endif
YENV = ENV = (CELL *)((B->cp_env)[E_E]);
B = B->cp_b;
SET_BB(B);
/* we have failed, and usually we would backtrack to this B,
trouble is, we may also have a delayed cut to do */
OldTopB = (choiceptr)(LCL0-MyOldTopB);
OldDelayedB = (choiceptr)(LCL0-MyOldDelayedB);
if (DelayedB != NULL) {
if (YOUNGER_CP(DelayedB,B)) {
/* we have a delayed cut to do */
if (YOUNGER_CP(OldTopB,DelayedB)) {
/* and this delayed cut is to before the c-code that actually called us */
B = OldTopB;
/* did we have a cut which was cutting more than our current cut? */
if (OldDelayedB != NULL && YOUNGER_CP(DelayedB,OldDelayedB))
DelayedB = OldDelayedB;
} else {
/* just cut back to where we should cut */
B = DelayedB;
DelayedB = OldDelayedB;
}
}
} else {
DelayedB = OldDelayedB;
}
TopB = OldTopB;
HB = PROTECT_FROZEN_H(B);
return(FALSE);
} else {
Error(SYSTEM_ERROR,TermNil,"emulator crashed");
return(FALSE);
}
}
int
RunTopGoal(Term t)
{
CODEADDR CodeAdr;
int arity;
Atom a;
Prop pe;
PredEntry *ppe;
CELL *pt;
if (IsAtomTerm(t)) {
arity = 0;
a = AtomOfTerm(t);
pt = NULL;
} else if (IsApplTerm(t)) {
Functor f = FunctorOfTerm(t);
if (IsBlobFunctor(f)) {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
arity = ArityOfFunctor(f);
a = NameOfFunctor(f);
/* I cannot use the standard macro here because
otherwise I would dereference the argument and
might skip a svar */
pt = RepAppl(t)+1;
} else {
Error(TYPE_ERROR_CALLABLE,t,"call/1");
return(FALSE);
}
pe = GetPredProp(a, arity);
ppe = RepPredProp(pe);
if (pe != NIL)
READ_LOCK(ppe->PRWLock);
if (pe == NIL ||
ppe->OpcodeOfPred == UNDEF_OPCODE ||
ppe->PredFlags & (UserCPredFlag|CPredFlag|BasicPredFlag) )
{
if (pe != NIL)
READ_UNLOCK(ppe->PRWLock);
/* we must always start the emulator with Prolog code */
return(FALSE);
}
CodeAdr = ppe->CodeOfPred;
READ_UNLOCK(ppe->PRWLock);
if (TrailTop - HeapTop < 2048) {
PrologMode = BootMode;
Error(SYSTEM_ERROR,TermNil,
"unable to boot because of too little heap space");
}
return(do_goal(CodeAdr, arity, pt, 0, TRUE));
}
static void
restore_regs(Term t)
{
if (IsApplTerm(t)) {
Int i;
Int max = ArityOfFunctor(FunctorOfTerm(t));
CELL *ptr = RepAppl(t)+1;
for (i = 0; i < max; i += 2) {
Int j = IntOfTerm(ptr[0]);
XREGS[j] = ptr[1];
ptr+=2;
}
}
}
/* low level voodoo to restore temporary registers after a call */
static Int
p_restore_regs(void)
{
Term t = Deref(ARG1);
if (IsVarTerm(t)) {
Error(INSTANTIATION_ERROR,t,"support for coroutining");
return(FALSE);
}
if (IsAtomTerm(t)) return(TRUE);
restore_regs(t);
return(TRUE);
}
/* low level voodoo to cut and then restore temporary registers after a call */
static Int
p_restore_regs2(void)
{
Term t = Deref(ARG1), d0;
choiceptr pt0;
if (IsVarTerm(t)) {
Error(INSTANTIATION_ERROR,t,"support for coroutining");
return(FALSE);
}
if (!IsAtomTerm(t)) {
restore_regs(t);
}
d0 = Deref(ARG2);
if (IsVarTerm(d0)) {
Error(INSTANTIATION_ERROR,d0,"support for coroutining");
return(FALSE);
}
#if SBA
if (!IsIntegerTerm(d0)) {
#else
if (!IsIntTerm(d0)) {
#endif
return(FALSE);
}
#if SBA
pt0 = (choiceptr)IntegerOfTerm(d0);
#else
pt0 = (choiceptr)(LCL0-IntOfTerm(d0));
#endif
if (TopB != NULL && YOUNGER_CP(TopB,pt0)) {
if (DelayedB == NULL || YOUNGER_CP(DelayedB,pt0))
DelayedB = pt0;
pt0 = TopB;
}
/* find where to cut to */
if (pt0 > B) {
/* Wow, we're gonna cut!!! */
#ifdef YAPOR
CUT_prune_to((choiceptr) d0);
#else
B = pt0;
#endif /* YAPOR */
HB = B->cp_h;
/* trim_trail();*/
}
return(TRUE);
}
static Int
p_clean_ifcp(void) {
#if SBA
choiceptr pt0 = (choiceptr)IntegerOfTerm(Deref(ARG1));
#else
choiceptr pt0 = (choiceptr)(LCL0-IntOfTerm(Deref(ARG1)));
#endif
if (pt0 == B) {
B = B->cp_b;
HB = B->cp_h;
} else {
pt0->cp_ap = (yamop *)TRUSTFAILCODE;
}
return(TRUE);
}
void
InitExecFs(void)
{
InitCPred("$execute", 1, p_execute, 0);
InitCPred("$execute_within", 3, p_execute_within, 0);
InitCPred("$execute", 2, p_at_execute, 0);
InitCPred("$call_with_args", 1, p_execute_0, 0);
InitCPred("$call_with_args", 2, p_execute_1, 0);
InitCPred("$call_with_args", 3, p_execute_2, 0);
InitCPred("$call_with_args", 4, p_execute_3, 0);
InitCPred("$call_with_args", 5, p_execute_4, 0);
InitCPred("$call_with_args", 6, p_execute_5, 0);
InitCPred("$call_with_args", 7, p_execute_6, 0);
InitCPred("$call_with_args", 8, p_execute_7, 0);
InitCPred("$call_with_args", 9, p_execute_8, 0);
InitCPred("$call_with_args", 10, p_execute_9, 0);
InitCPred("$call_with_args", 11, p_execute_10, 0);
#ifdef DEPTH_LIMIT
InitCPred("$execute_under_depth_limit", 2, p_execute_depth_limit, 0);
#endif
InitCPred("$execute0", 1, p_execute0, 0);
InitCPred("$save_current_choice_point", 1, p_save_cp, 0);
InitCPred("$pred_goal_expansion_on", 0, p_pred_goal_expansion_on, SafePredFlag);
InitCPred("$restore_regs", 1, p_restore_regs, SafePredFlag);
InitCPred("$restore_regs", 2, p_restore_regs2, SafePredFlag);
InitCPred("$clean_ifcp", 1, p_clean_ifcp, SafePredFlag);
}