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yap-6.3/H/trim_trail.h
2014-01-19 21:15:05 +00:00

172 lines
4.2 KiB
C

#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 == LOCAL_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 (IN_BETWEEN(LOCAL_TrailBase, pt, LOCAL_TrailTop)) {
/* skip, this is a problem because we lose information,
namely active references */
pt1 = (tr_fr_ptr)pt;
} else if (IN_BETWEEN(H0,pt,HR) && IsAttVar(pt)) {
CELL val = Deref(*pt);
if (IsVarTerm(val)) {
Bind(pt, MkAtomTerm(AtomCut));
Yap_WakeUp(pt);
}
} else if ((*pt & (LogUpdMask|IndexMask)) == (LogUpdMask|IndexMask)) {
LogUpdIndex *cl = ClauseFlagsToLogUpdIndex(pt);
int erase;
#if defined(THREADS) || defined(YAPOR)
PredEntry *ap = cl->ClPred;
#endif
LOCK(ap->PELock);
DEC_CLREF_COUNT(cl);
cl->ClFlags &= ~InUseMask;
erase = (cl->ClFlags & (ErasedMask|DirtyMask)) && !(cl->ClRefCount);
if (erase) {
/* at this point, we are the only ones accessing the clause,
hence we don't need to have a lock it */
if (cl->ClFlags & ErasedMask)
Yap_ErLogUpdIndex(cl);
else
Yap_CleanUpIndex(cl);
}
UNLOCK(ap->PELock);
} 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;
memmove(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 (IN_BETWEEN(H0,pt,H) && IsAttVar(pt)) {
CELL val = Deref(*pt);
if (IsVarTerm(val)) {
Bind(VarOfTerm(val), MkAtomTerm(AtomCut));
Yap_WakeUp(pt);
}
} else if ((*pt & (LogUpdMask|IndexMask)) == (LogUpdMask|IndexMask)) {
LogUpdIndex *cl = ClauseFlagsToLogUpdIndex(pt);
#if defined(YAPOR) || defined(THREADS)
PredEntry *ap = cl->ClPred;
#endif
int erase;
LOCK(ap->PELock);
DEC_CLREF_COUNT(cl);
cl->ClFlags &= ~InUseMask;
erase = (cl->ClFlags & (DirtyMask|ErasedMask)) && !(cl->ClRefCount);
if (erase) {
/* at this point, we are the only ones accessing the clause,
hence we don't need to have a lock it */
if (cl->ClFlags & ErasedMask)
Yap_ErLogUpdIndex(cl);
else
Yap_CleanUpIndex(cl);
}
UNLOCK(ap->PELock);
} else {
TrailTerm(pt0) = d1;
pt0++;
}
pt1++;
} else {
TrailTerm(pt0) = d1;
pt0++;
pt1++;
}
ENDD(d1);
}
TR = pt0;
}
#endif /* FROZEN_STACKS */