The second part of picosat.c
Signed-off-by: Patrick Franz <deltaone@xxxxxxxxxx>
Signed-off-by: Ibrahim Fayaz <phayax@xxxxxxxxx>
Signed-off-by: Thorsten Berger <thorsten.berger@xxxxxx>
Signed-off-by: Ole Schuerks <ole0811sch@xxxxxxxxx>
---
scripts/kconfig/picosat.c | 3000 +++++++++++++++++++++++++++++++++++++
1 file changed, 3000 insertions(+)
diff --git a/scripts/kconfig/picosat.c b/scripts/kconfig/picosat.c
index 872a38b335c4..c183dffb89a3 100644
--- a/scripts/kconfig/picosat.c
+++ b/scripts/kconfig/picosat.c
@@ -2998,3 +2998,3003 @@ unassign (PS * ps, Lit * lit)
{
other = p->lits[1];
q = p->next + 1;
+ }
+ else
+ {
+ assert (p->lits[1] == lit);
+ q = p->next;
+ }
+
+ next = *q;
+ *q = *LIT2HTPS (other);
+ *LIT2HTPS (other) = p;
+ p = next;
+ }
+ }
+#endif
+
+#ifndef NADC
+ if (v->adotabpos)
+ {
+ assert (ps->nadotab);
+ assert (*v->adotabpos == v->ado);
+
+ *v->adotabpos = 0;
+ v->adotabpos = 0;
+
+ ps->nadotab--;
+ }
+#endif
+}
+
+static Cls *
+var2reason (PS * ps, Var * var)
+{
+ Cls * res = var->reason;
+#ifdef NO_BINARY_CLAUSES
+ Lit * this, * other;
+ if (ISLITREASON (res))
+ {
+ this = VAR2LIT (var);
+ if (this->val == FALSE)
+ this = NOTLIT (this);
+
+ other = REASON2LIT (res);
+ assert (other->val == TRUE);
+ assert (this->val == TRUE);
+ res = setimpl (ps, NOTLIT (other), this);
+ }
+#else
+ (void) ps;
+#endif
+ return res;
+}
+
+static void
+mark_clause_to_be_collected (Cls * c)
+{
+ assert (!c->collect);
+ c->collect = 1;
+}
+
+static void
+undo (PS * ps, unsigned new_level)
+{
+ Lit *lit;
+ Var *v;
+
+ while (ps->thead > ps->trail)
+ {
+ lit = *--ps->thead;
+ v = LIT2VAR (lit);
+ if (v->level == new_level)
+ {
+ ps->thead++; /* fix pre decrement */
+ break;
+ }
+
+ unassign (ps, lit);
+ }
+
+ ps->LEVEL = new_level;
+ ps->ttail = ps->thead;
+ ps->ttail2 = ps->thead;
+#ifndef NADC
+ ps->ttailado = ps->thead;
+#endif
+
+#ifdef NO_BINARY_CLAUSES
+ if (ps->conflict == &ps->cimpl)
+ resetcimpl (ps);
+#endif
+#ifndef NADC
+ if (ps->conflict && ps->conflict == ps->adoconflict)
+ resetadoconflict (ps);
+#endif
+ ps->conflict = ps->mtcls;
+ if (ps->LEVEL < ps->adecidelevel)
+ {
+ assert (ps->als < ps->alshead);
+ ps->adecidelevel = 0;
+ ps->alstail = ps->als;
+ }
+ LOG ( fprintf (ps->out, "%sback to level %u\n", ps->prefix, ps->LEVEL));
+}
+
+#ifndef NDEBUG
+
+static int
+clause_satisfied (Cls * c)
+{
+ Lit **p, **eol, *lit;
+
+ eol = end_of_lits (c);
+ for (p = c->lits; p < eol; p++)
+ {
+ lit = *p;
+ if (lit->val == TRUE)
+ return 1;
+ }
+
+ return 0;
+}
+
+static void
+original_clauses_satisfied (PS * ps)
+{
+ Cls **p, *c;
+
+ for (p = ps->oclauses; p < ps->ohead; p++)
+ {
+ c = *p;
+
+ if (!c)
+ continue;
+
+ if (c->learned)
+ continue;
+
+ assert (clause_satisfied (c));
+ }
+}
+
+static void
+assumptions_satisfied (PS * ps)
+{
+ Lit *lit, ** p;
+
+ for (p = ps->als; p < ps->alshead; p++)
+ {
+ lit = *p;
+ assert (lit->val == TRUE);
+ }
+}
+
+#endif
+
+static void
+sflush (PS * ps)
+{
+ double now = picosat_time_stamp ();
+ double delta = now - ps->entered;
+ delta = (delta < 0) ? 0 : delta;
+ ps->seconds += delta;
+ ps->entered = now;
+}
+
+static double
+mb (PS * ps)
+{
+ return ps->current_bytes / (double) (1 << 20);
+}
+
+static double
+avglevel (PS * ps)
+{
+ return ps->decisions ? ps->levelsum / ps->decisions : 0.0;
+}
+
+static void
+rheader (PS * ps)
+{
+ assert (ps->lastrheader <= ps->reports);
+
+ if (ps->lastrheader == ps->reports)
+ return;
+
+ ps->lastrheader = ps->reports;
+
+ fprintf (ps->out, "%s\n", ps->prefix);
+ fprintf (ps->out, "%s %s\n", ps->prefix, ps->rline[0]);
+ fprintf (ps->out, "%s %s\n", ps->prefix, ps->rline[1]);
+ fprintf (ps->out, "%s\n", ps->prefix);
+}
+
+static unsigned
+dynamic_flips_per_assignment_per_mille (PS * ps)
+{
+ assert (FFLIPPEDPREC >= 1000);
+ return ps->sdflips / (FFLIPPEDPREC / 1000);
+}
+
+#ifdef NLUBY
+
+static int
+high_agility (PS * ps)
+{
+ return dynamic_flips_per_assignment_per_mille (ps) >= 200;
+}
+
+static int
+very_high_agility (PS * ps)
+{
+ return dynamic_flips_per_assignment_per_mille (ps) >= 250;
+}
+
+#else
+
+static int
+medium_agility (PS * ps)
+{
+ return dynamic_flips_per_assignment_per_mille (ps) >= 230;
+}
+
+#endif
+
+static void
+relemdata (PS * ps)
+{
+ char *p;
+ int x;
+
+ if (ps->reports < 0)
+ {
+ /* strip trailing white space
+ */
+ for (x = 0; x <= 1; x++)
+ {
+ p = ps->rline[x] + strlen (ps->rline[x]);
+ while (p-- > ps->rline[x])
+ {
+ if (*p != ' ')
+ break;
+
+ *p = 0;
+ }
+ }
+
+ rheader (ps);
+ }
+ else
+ fputc ('\n', ps->out);
+
+ ps->RCOUNT = 0;
+}
+
+static void
+relemhead (PS * ps, const char * name, int fp, double val)
+{
+ int x, y, len, size;
+ const char *fmt;
+ unsigned tmp, e;
+
+ if (ps->reports < 0)
+ {
+ x = ps->RCOUNT & 1;
+ y = (ps->RCOUNT / 2) * 12 + x * 6;
+
+ if (ps->RCOUNT == 1)
+ sprintf (ps->rline[1], "%6s", "");
+
+ len = strlen (name);
+ while (ps->szrline <= len + y + 1)
+ {
+ size = ps->szrline ? 2 * ps->szrline : 128;
+ ps->rline[0] = resize (ps, ps->rline[0], ps->szrline, size);
+ ps->rline[1] = resize (ps, ps->rline[1], ps->szrline, size);
+ ps->szrline = size;
+ }
+
+ fmt = (len <= 6) ? "%6s%10s" : "%-10s%4s";
+ sprintf (ps->rline[x] + y, fmt, name, "");
+ }
+ else if (val < 0)
+ {
+ assert (fp);
+
+ if (val > -100 && (tmp = val * 10.0 - 0.5) > -1000.0)
+ {
+ fprintf (ps->out, "-%4.1f ", -tmp / 10.0);
+ }
+ else
+ {
+ tmp = -val / 10.0 + 0.5;
+ e = 1;
+ while (tmp >= 100)
+ {
+ tmp /= 10;
+ e++;
+ }
+
+ fprintf (ps->out, "-%2ue%u ", tmp, e);
+ }
+ }
+ else
+ {
+ if (fp && val < 1000 && (tmp = val * 10.0 + 0.5) < 10000)
+ {
+ fprintf (ps->out, "%5.1f ", tmp / 10.0);
+ }
+ else if (!fp && (tmp = val) < 100000)
+ {
+ fprintf (ps->out, "%5u ", tmp);
+ }
+ else
+ {
+ tmp = val / 10.0 + 0.5;
+ e = 1;
+
+ while (tmp >= 1000)
+ {
+ tmp /= 10;
+ e++;
+ }
+
+ fprintf (ps->out, "%3ue%u ", tmp, e);
+ }
+ }
+
+ ps->RCOUNT++;
+}
+
+inline static void
+relem (PS * ps, const char *name, int fp, double val)
+{
+ if (name)
+ relemhead (ps, name, fp, val);
+ else
+ relemdata (ps);
+}
+
+static unsigned
+reduce_limit_on_lclauses (PS * ps)
+{
+ unsigned res = ps->lreduce;
+ res += ps->llocked;
+ return res;
+}
+
+static void
+report (PS * ps, int replevel, char type)
+{
+ int rounds;
+
+#ifdef RCODE
+ (void) type;
+#endif
+
+ if (ps->verbosity < replevel)
+ return;
+
+ sflush (ps);
+
+ if (!ps->reports)
+ ps->reports = -1;
+
+ for (rounds = (ps->reports < 0) ? 2 : 1; rounds; rounds--)
+ {
+ if (ps->reports >= 0)
+ fprintf (ps->out, "%s%c ", ps->prefix, type);
+
+ relem (ps, "seconds", 1, ps->seconds);
+ relem (ps, "level", 1, avglevel (ps));
+ assert (ps->fixed <= ps->max_var);
+ relem (ps, "variables", 0, ps->max_var - ps->fixed);
+ relem (ps, "used", 1, PERCENT (ps->vused, ps->max_var));
+ relem (ps, "original", 0, ps->noclauses);
+ relem (ps, "conflicts", 0, ps->conflicts);
+ // relem (ps, "decisions", 0, ps->decisions);
+ // relem (ps, "conf/dec", 1, PERCENT(ps->conflicts,ps->decisions));
+ // relem (ps, "limit", 0, reduce_limit_on_lclauses (ps));
+ relem (ps, "learned", 0, ps->nlclauses);
+ // relem (ps, "limit", 1, PERCENT (ps->nlclauses, reduce_limit_on_lclauses (ps)));
+ relem (ps, "limit", 0, ps->lreduce);
+#ifdef STATS
+ relem (ps, "learning", 1, PERCENT (ps->llused, ps->lladded));
+#endif
+ relem (ps, "agility", 1, dynamic_flips_per_assignment_per_mille (ps) / 10.0);
+ // relem (ps, "original", 0, ps->noclauses);
+ relem (ps, "MB", 1, mb (ps));
+ // relem (ps, "lladded", 0, ps->lladded);
+ // relem (ps, "llused", 0, ps->llused);
+
+ relem (ps, 0, 0, 0);
+
+ ps->reports++;
+ }
+
+ /* Adapt this to the number of rows in your terminal.
+ */
+ #define ROWS 25
+
+ if (ps->reports % (ROWS - 3) == (ROWS - 4))
+ rheader (ps);
+
+ fflush (ps->out);
+}
+
+static int
+bcp_queue_is_empty (PS * ps)
+{
+ if (ps->ttail != ps->thead)
+ return 0;
+
+ if (ps->ttail2 != ps->thead)
+ return 0;
+
+#ifndef NADC
+ if (ps->ttailado != ps->thead)
+ return 0;
+#endif
+
+ return 1;
+}
+
+static int
+satisfied (PS * ps)
+{
+ assert (!ps->mtcls);
+ assert (!ps->failed_assumption);
+ if (ps->alstail < ps->alshead)
+ return 0;
+ assert (!ps->conflict);
+ assert (bcp_queue_is_empty (ps));
+ return ps->thead == ps->trail + ps->max_var; /* all assigned */
+}
+
+static void
+vrescore (PS * ps)
+{
+ Rnk *p, *eor = ps->rnks + ps->max_var;
+ for (p = ps->rnks + 1; p <= eor; p++)
+ if (p->score != INFFLT)
+ p->score = mulflt (p->score, ps->ilvinc);
+ ps->vinc = mulflt (ps->vinc, ps->ilvinc);;
+#ifdef VISCORES
+ ps->nvinc = mulflt (ps->nvinc, ps->lscore);;
+#endif
+}
+
+static void
+inc_score (PS * ps, Var * v)
+{
+ Flt score;
+ Rnk *r;
+
+#ifndef NFL
+ if (ps->simplifying)
+ return;
+#endif
+
+ if (!v->level)
+ return;
+
+ if (v->internal)
+ return;
+
+ r = VAR2RNK (v);
+ score = r->score;
+
+ assert (score != INFFLT);
+
+ score = addflt (score, ps->vinc);
+ assert (score < INFFLT);
+ r->score = score;
+ if (r->pos > 0)
+ hup (ps, r);
+
+ if (score > ps->lscore)
+ vrescore (ps);
+}
+
+static void
+inc_activity (PS * ps, Cls * c)
+{
+ Act *p;
+
+ if (!c->learned)
+ return;
+
+ if (c->size <= 2)
+ return;
+
+ p = CLS2ACT (c);
+ *p = addflt (*p, ps->cinc);
+}
+
+static unsigned
+hashlevel (unsigned l)
+{
+ return 1u << (l & 31);
+}
+
+static void
+push (PS * ps, Var * v)
+{
+ if (ps->dhead == ps->eod)
+ ENLARGE (ps->dfs, ps->dhead, ps->eod);
+
+ *ps->dhead++ = v;
+}
+
+static Var *
+pop (PS * ps)
+{
+ assert (ps->dfs < ps->dhead);
+ return *--ps->dhead;
+}
+
+static void
+analyze (PS * ps)
+{
+ unsigned open, minlevel, siglevels, l, old, i, orig;
+ Lit *this, *other, **p, **q, **eol;
+ Var *v, *u, **m, *start, *uip;
+ Cls *c;
+
+ assert (ps->conflict);
+
+ assert (ps->ahead == ps->added);
+ assert (ps->mhead == ps->marked);
+ assert (ps->rhead == ps->resolved);
+
+ /* First, search for First UIP variable and mark all resolved variables.
+ * At the same time determine the minimum decision level involved.
+ * Increase activities of resolved variables.
+ */
+ q = ps->thead;
+ open = 0;
+ minlevel = ps->LEVEL;
+ siglevels = 0;
+ uip = 0;
+
+ c = ps->conflict;
+
+ for (;;)
+ {
+ add_antecedent (ps, c);
+ inc_activity (ps, c);
+ eol = end_of_lits (c);
+ for (p = c->lits; p < eol; p++)
+ {
+ other = *p;
+
+ if (other->val == TRUE)
+ continue;
+
+ assert (other->val == FALSE);
+
+ u = LIT2VAR (other);
+ if (u->mark)
+ continue;
+
+ u->mark = 1;
+ inc_score (ps, u);
+ use_var (ps, u);
+
+ if (u->level == ps->LEVEL)
+ {
+ open++;
+ }
+ else
+ {
+ push_var_as_marked (ps, u);
+
+ if (u->level)
+ {
+ /* The statistics counter 'nonminimizedllits' sums up the
+ * number of literals that would be added if only the
+ * 'first UIP' scheme for learned clauses would be used
+ * and no clause minimization.
+ */
+ ps->nonminimizedllits++;
+
+ if (u->level < minlevel)
+ minlevel = u->level;
+
+ siglevels |= hashlevel (u->level);
+ }
+ else
+ {
+ assert (!u->level);
+ assert (u->reason);
+ }
+ }
+ }
+
+ do
+ {
+ if (q == ps->trail)
+ {
+ uip = 0;
+ goto DONE_FIRST_UIP;
+ }
+
+ this = *--q;
+ uip = LIT2VAR (this);
+ }
+ while (!uip->mark);
+
+ uip->mark = 0;
+
+ c = var2reason (ps, uip);
+#ifdef NO_BINARY_CLAUSES
+ if (c == &ps->impl)
+ resetimpl (ps);
+#endif
+ open--;
+ if ((!open && ps->LEVEL) || !c)
+ break;
+
+ assert (c);
+ }
+
+DONE_FIRST_UIP:
+
+ if (uip)
+ {
+ assert (ps->LEVEL);
+ this = VAR2LIT (uip);
+ this += (this->val == TRUE);
+ ps->nonminimizedllits++;
+ ps->minimizedllits++;
+ add_lit (ps, this);
+#ifdef STATS
+ if (uip->reason)
+ ps->uips++;
+#endif
+ }
+ else
+ assert (!ps->LEVEL);
+
+ /* Second, try to mark more intermediate variables, with the goal to
+ * minimize the conflict clause. This is a DFS from already marked
+ * variables backward through the implication graph. It tries to reach
+ * other marked variables. If the search reaches an unmarked decision
+ * variable or a variable assigned below the minimum level of variables in
+ * the first uip learned clause or a level on which no variable has been
+ * marked, then the variable from which the DFS is started is not
+ * redundant. Otherwise the start variable is redundant and will
+ * eventually be removed from the learned clause in step 4. We initially
+ * implemented BFS, but then profiling revelead that this step is a bottle
+ * neck for certain incremental applications. After switching to DFS this
+ * hot spot went away.
+ */
+ orig = ps->mhead - ps->marked;
+ for (i = 0; i < orig; i++)
+ {
+ start = ps->marked[i];
+
+ assert (start->mark);
+ assert (start != uip);
+ assert (start->level < ps->LEVEL);
+
+ if (!start->reason)
+ continue;
+
+ old = ps->mhead - ps->marked;
+ assert (ps->dhead == ps->dfs);
+ push (ps, start);
+
+ while (ps->dhead > ps->dfs)
+ {
+ u = pop (ps);
+ assert (u->mark);
+
+ c = var2reason (ps, u);
+#ifdef NO_BINARY_CLAUSES
+ if (c == &ps->impl)
+ resetimpl (ps);
+#endif
+ if (!c ||
+ ((l = u->level) &&
+ (l < minlevel || ((hashlevel (l) & ~siglevels)))))
+ {
+ while (ps->mhead > ps->marked + old) /* reset all marked */
+ (*--ps->mhead)->mark = 0;
+
+ ps->dhead = ps->dfs; /* and DFS stack */
+ break;
+ }
+
+ eol = end_of_lits (c);
+ for (p = c->lits; p < eol; p++)
+ {
+ v = LIT2VAR (*p);
+ if (v->mark)
+ continue;
+
+ mark_var (ps, v);
+ push (ps, v);
+ }
+ }
+ }
+
+ for (m = ps->marked; m < ps->mhead; m++)
+ {
+ v = *m;
+
+ assert (v->mark);
+ assert (!v->resolved);
+
+ use_var (ps, v);
+
+ c = var2reason (ps, v);
+ if (!c)
+ continue;
+
+#ifdef NO_BINARY_CLAUSES
+ if (c == &ps->impl)
+ resetimpl (ps);
+#endif
+ eol = end_of_lits (c);
+ for (p = c->lits; p < eol; p++)
+ {
+ other = *p;
+
+ u = LIT2VAR (other);
+ if (!u->level)
+ continue;
+
+ if (!u->mark) /* 'MARKTEST' */
+ break;
+ }
+
+ if (p != eol)
+ continue;
+
+ add_antecedent (ps, c);
+ v->resolved = 1;
+ }
+
+ for (m = ps->marked; m < ps->mhead; m++)
+ {
+ v = *m;
+
+ assert (v->mark);
+ v->mark = 0;
+
+ if (v->resolved)
+ {
+ v->resolved = 0;
+ continue;
+ }
+
+ this = VAR2LIT (v);
+ if (this->val == TRUE)
+ this++; /* actually NOTLIT */
+
+ add_lit (ps, this);
+ ps->minimizedllits++;
+ }
+
+ assert (ps->ahead <= ps->eoa);
+ assert (ps->rhead <= ps->eor);
+
+ ps->mhead = ps->marked;
+}
+
+static void
+fanalyze (PS * ps)
+{
+ Lit ** eol, ** p, * lit;
+ Cls * c, * reason;
+ Var * v, * u;
+ int next;
+
+#ifndef RCODE
+ double start = picosat_time_stamp ();
+#endif
+
+ assert (ps->failed_assumption);
+ assert (ps->failed_assumption->val == FALSE);
+
+ v = LIT2VAR (ps->failed_assumption);
+ reason = var2reason (ps, v);
+ if (!reason) return;
+#ifdef NO_BINARY_CLAUSES
+ if (reason == &ps->impl)
+ resetimpl (ps);
+#endif
+
+ eol = end_of_lits (reason);
+ for (p = reason->lits; p != eol; p++)
+ {
+ lit = *p;
+ u = LIT2VAR (lit);
+ if (u == v) continue;
+ if (u->reason) break;
+ }
+ if (p == eol) return;
+
+ assert (ps->ahead == ps->added);
+ assert (ps->mhead == ps->marked);
+ assert (ps->rhead == ps->resolved);
+
+ next = 0;
+ mark_var (ps, v);
+ add_lit (ps, NOTLIT (ps->failed_assumption));
+
+ do
+ {
+ v = ps->marked[next++];
+ use_var (ps, v);
+ if (v->reason)
+ {
+ reason = var2reason (ps, v);
+#ifdef NO_BINARY_CLAUSES
+ if (reason == &ps->impl)
+ resetimpl (ps);
+#endif
+ add_antecedent (ps, reason);
+ eol = end_of_lits (reason);
+ for (p = reason->lits; p != eol; p++)
+ {
+ lit = *p;
+ u = LIT2VAR (lit);
+ if (u == v) continue;
+ if (u->mark) continue;
+ mark_var (ps, u);
+ }
+ }
+ else
+ {
+ lit = VAR2LIT (v);
+ if (lit->val == TRUE) lit = NOTLIT (lit);
+ add_lit (ps, lit);
+ }
+ }
+ while (ps->marked + next < ps->mhead);
+
+ c = add_simplified_clause (ps, 1);
+ v = LIT2VAR (ps->failed_assumption);
+ reason = v->reason;
+#ifdef NO_BINARY_CLAUSES
+ if (!ISLITREASON (reason))
+#endif
+ {
+ assert (reason->locked);
+ reason->locked = 0;
+ if (reason->learned && reason->size > 2)
+ {
+ assert (ps->llocked > 0);
+ ps->llocked--;
+ }
+ }
+
+#ifdef NO_BINARY_CLAUSES
+ if (c == &ps->impl)
+ {
+ c = impl2reason (ps, NOTLIT (ps->failed_assumption));
+ }
+ else
+#endif
+ {
+ assert (c->learned);
+ assert (!c->locked);
+ c->locked = 1;
+ if (c->size > 2)
+ {
+ ps->llocked++;
+ assert (ps->llocked > 0);
+ }
+ }
+
+ v->reason = c;
+
+ while (ps->mhead > ps->marked)
+ (*--ps->mhead)->mark = 0;
+
+ if (ps->verbosity)
+ fprintf (ps->out, "%sfanalyze took %.1f seconds\n",
+ ps->prefix, picosat_time_stamp () - start);
+}
+
+/* Propagate assignment of 'this' to 'FALSE' by visiting all binary clauses in
+ * which 'this' occurs.
+ */
+inline static void
+prop2 (PS * ps, Lit * this)
+{
+#ifdef NO_BINARY_CLAUSES
+ Lit ** l, ** start;
+ Ltk * lstk;
+#else
+ Cls * c, ** p;
+ Cls * next;
+#endif
+ Lit * other;
+ Val tmp;
+
+ assert (this->val == FALSE);
+
+#ifdef NO_BINARY_CLAUSES
+ lstk = LIT2IMPLS (this);
+ start = lstk->start;
+ l = start + lstk->count;
+ while (l != start)
+ {
+ /* The counter 'visits' is the number of clauses that are
+ * visited during propagations of assignments.
+ */
+ ps->visits++;
+#ifdef STATS
+ ps->bvisits++;
+#endif
+ other = *--l;
+ tmp = other->val;
+
+ if (tmp == TRUE)
+ {
+#ifdef STATS
+ ps->othertrue++;
+ ps->othertrue2++;
+ if (LIT2VAR (other)->level < ps->LEVEL)
+ ps->othertrue2u++;
+#endif
+ continue;
+ }
+
+ if (tmp != FALSE)
+ {
+ assign_forced (ps, other, LIT2REASON (NOTLIT(this)));
+ continue;
+ }
+
+ if (ps->conflict == &ps->cimpl)
+ resetcimpl (ps);
+ ps->conflict = setcimpl (ps, this, other);
+ }
+#else
+ /* Traverse all binary clauses with 'this'. Head/Tail pointers for binary
+ * clauses do not have to be modified here.
+ */
+ p = LIT2IMPLS (this);
+ for (c = *p; c; c = next)
+ {
+ ps->visits++;
+#ifdef STATS
+ ps->bvisits++;
+#endif
+ assert (!c->collect);
+#ifdef TRACE
+ assert (!c->collected);
+#endif
+ assert (c->size == 2);
+
+ other = c->lits[0];
+ if (other == this)
+ {
+ next = c->next[0];
+ other = c->lits[1];
+ }
+ else
+ next = c->next[1];
+
+ tmp = other->val;
+
+ if (tmp == TRUE)
+ {
+#ifdef STATS
+ ps->othertrue++;
+ ps->othertrue2++;
+ if (LIT2VAR (other)->level < ps->LEVEL)
+ ps->othertrue2u++;
+#endif
+ continue;
+ }
+
+ if (tmp == FALSE)
+ ps->conflict = c;
+ else
+ assign_forced (ps, other, c); /* unit clause */
+ }
+#endif /* !defined(NO_BINARY_CLAUSES) */
+}
+
+#ifndef NDSC
+static int
+should_disconnect_head_tail (PS * ps, Lit * lit)
+{
+ unsigned litlevel;
+ Var * v;
+
+ assert (lit->val == TRUE);
+
+ v = LIT2VAR (lit);
+ litlevel = v->level;
+
+ if (!litlevel)
+ return 1;
+
+#ifndef NFL
+ if (ps->simplifying)
+ return 0;
+#endif
+
+ return litlevel < ps->LEVEL;
+}
+#endif
+
+inline static void
+propl (PS * ps, Lit * this)
+{
+ Lit **l, *other, *prev, *new_lit, **eol;
+ Cls *next, **htp_ptr, **new_htp_ptr;
+ Cls *c;
+#ifdef STATS
+ unsigned size;
+#endif
+
+ htp_ptr = LIT2HTPS (this);
+ assert (this->val == FALSE);
+
+ /* Traverse all non binary clauses with 'this'. Head/Tail pointers are
+ * updated as well.
+ */
+ for (c = *htp_ptr; c; c = next)
+ {
+ ps->visits++;
+#ifdef STATS
+ size = c->size;
+ assert (size >= 3);
+ ps->traversals++; /* other is dereferenced at least */
+
+ if (size == 3)
+ ps->tvisits++;
+ else if (size >= 4)
+ {
+ ps->lvisits++;
+ ps->ltraversals++;
+ }
+#endif
+#ifdef TRACE
+ assert (!c->collected);
+#endif
+ assert (c->size > 0);
+
+ other = c->lits[0];
+ if (other != this)
+ {
+ assert (c->size != 1);
+ c->lits[0] = this;
+ c->lits[1] = other;
+ next = c->next[1];
+ c->next[1] = c->next[0];
+ c->next[0] = next;
+ }
+ else if (c->size == 1) /* With assumptions we need to
+ * traverse unit clauses as well.
+ */
+ {
+ assert (!ps->conflict);
+ ps->conflict = c;
+ break;
+ }
+ else
+ {
+ assert (other == this && c->size > 1);
+ other = c->lits[1];
+ next = c->next[0];
+ }
+ assert (other == c->lits[1]);
+ assert (this == c->lits[0]);
+ assert (next == c->next[0]);
+ assert (!c->collect);
+
+ if (other->val == TRUE)
+ {
+#ifdef STATS
+ ps->othertrue++;
+ ps->othertruel++;
+#endif
+#ifndef NDSC
+ if (should_disconnect_head_tail (ps, other))
+ {
+ new_htp_ptr = LIT2DHTPS (other);
+ c->next[0] = *new_htp_ptr;
+ *new_htp_ptr = c;
+#ifdef STATS
+ ps->othertruelu++;
+#endif
+ *htp_ptr = next;
+ continue;
+ }
+#endif
+ htp_ptr = c->next;
+ continue;
+ }
+
+ l = c->lits + 1;
+ eol = (Lit**) c->lits + c->size;
+ prev = this;
+
+ while (++l != eol)
+ {
+#ifdef STATS
+ if (size >= 3)
+ {
+ ps->traversals++;
+ if (size > 3)
+ ps->ltraversals++;
+ }
+#endif
+ new_lit = *l;
+ *l = prev;
+ prev = new_lit;
+ if (new_lit->val != FALSE) break;
+ }
+
+ if (l == eol)
+ {
+ while (l > c->lits + 2)
+ {
+ new_lit = *--l;
+ *l = prev;
+ prev = new_lit;
+ }
+ assert (c->lits[0] == this);
+
+ assert (other == c->lits[1]);
+ if (other->val == FALSE) /* found conflict */
+ {
+ assert (!ps->conflict);
+ ps->conflict = c;
+ return;
+ }
+
+ assign_forced (ps, other, c); /* unit clause */
+ htp_ptr = c->next;
+ }
+ else
+ {
+ assert (new_lit->val == TRUE || new_lit->val == UNDEF);
+ c->lits[0] = new_lit;
+ // *l = this;
+ new_htp_ptr = LIT2HTPS (new_lit);
+ c->next[0] = *new_htp_ptr;
+ *new_htp_ptr = c;
+ *htp_ptr = next;
+ }
+ }
+}
+
+#ifndef NADC
+
+static unsigned primes[] = { 996293, 330643, 753947, 500873 };
+
+#define PRIMES ((sizeof primes)/sizeof *primes)
+
+static unsigned
+hash_ado (PS * ps, Lit ** ado, unsigned salt)
+{
+ unsigned i, res, tmp;
+ Lit ** p, * lit;
+
+ assert (salt < PRIMES);
+
+ i = salt;
+ res = 0;
+
+ for (p = ado; (lit = *p); p++)
+ {
+ assert (lit->val);
+
+ tmp = res >> 31;
+ res <<= 1;
+
+ if (lit->val > 0)
+ res |= 1;
+
+ assert (i < PRIMES);
+ res *= primes[i++];
+ if (i == PRIMES)
+ i = 0;
+
+ res += tmp;
+ }
+
+ return res & (ps->szadotab - 1);
+}
+
+static unsigned
+cmp_ado (Lit ** a, Lit ** b)
+{
+ Lit ** p, ** q, * l, * k;
+ int res;
+
+ for (p = a, q = b; (l = *p); p++, q++)
+ {
+ k = *q;
+ assert (k);
+ if ((res = (l->val - k->val)))
+ return res;
+ }
+
+ assert (!*q);
+
+ return 0;
+}
+
+static Lit ***
+find_ado (PS * ps, Lit ** ado)
+{
+ Lit *** res, ** other;
+ unsigned pos, delta;
+
+ pos = hash_ado (ps, ado, 0);
+ assert (pos < ps->szadotab);
+ res = ps->adotab + pos;
+
+ other = *res;
+ if (!other || !cmp_ado (other, ado))
+ return res;
+
+ delta = hash_ado (ps, ado, 1);
+ if (!(delta & 1))
+ delta++;
+
+ assert (delta & 1);
+ assert (delta < ps->szadotab);
+
+ for (;;)
+ {
+ pos += delta;
+ if (pos >= ps->szadotab)
+ pos -= ps->szadotab;
+
+ assert (pos < ps->szadotab);
+ res = ps->adotab + pos;
+ other = *res;
+ if (!other || !cmp_ado (other, ado))
+ return res;
+ }
+}
+
+static void
+enlarge_adotab (PS * ps)
+{
+ /* TODO make this generic */
+
+ ABORTIF (ps->szadotab,
+ "internal: all different objects table needs larger initial size");
+ assert (!ps->nadotab);
+ ps->szadotab = 10000;
+ NEWN (ps->adotab, ps->szadotab);
+ CLRN (ps->adotab, ps->szadotab);
+}
+
+static int
+propado (PS * ps, Var * v)
+{
+ Lit ** p, ** q, *** adotabpos, **ado, * lit;
+ Var * u;
+
+ if (ps->LEVEL && ps->adodisabled)
+ return 1;
+
+ assert (!ps->conflict);
+ assert (!ps->adoconflict);
+ assert (VAR2LIT (v)->val != UNDEF);
+ assert (!v->adotabpos);
+
+ if (!v->ado)
+ return 1;
+
+ assert (v->inado);
+
+ for (p = v->ado; (lit = *p); p++)
+ if (lit->val == UNDEF)
+ {
+ u = LIT2VAR (lit);
+ assert (!u->ado);
+ u->ado = v->ado;
+ v->ado = 0;
+
+ return 1;
+ }
+
+ if (4 * ps->nadotab >= 3 * ps->szadotab) /* at least 75% filled */
+ enlarge_adotab (ps);
+
+ adotabpos = find_ado (ps, v->ado);
+ ado = *adotabpos;
+
+ if (!ado)
+ {
+ ps->nadotab++;
+ v->adotabpos = adotabpos;
+ *adotabpos = v->ado;
+ return 1;
+ }
+
+ assert (ado != v->ado);
+
+ ps->adoconflict = new_clause (ps, 2 * llength (ado), 1);
+ q = ps->adoconflict->lits;
+
+ for (p = ado; (lit = *p); p++)
+ *q++ = lit->val == FALSE ? lit : NOTLIT (lit);
+
+ for (p = v->ado; (lit = *p); p++)
+ *q++ = lit->val == FALSE ? lit : NOTLIT (lit);
+
+ assert (q == ENDOFCLS (ps->adoconflict));
+ ps->conflict = ps->adoconflict;
+ ps->adoconflicts++;
+ return 0;
+}
+
+#endif
+
+static void
+bcp (PS * ps)
+{
+ int props = 0;
+ assert (!ps->conflict);
+
+ if (ps->mtcls)
+ return;
+
+ for (;;)
+ {
+ if (ps->ttail2 < ps->thead) /* prioritize implications */
+ {
+ props++;
+ prop2 (ps, NOTLIT (*ps->ttail2++));
+ }
+ else if (ps->ttail < ps->thead) /* unit clauses or clauses with length > 2 */
+ {
+ if (ps->conflict) break;
+ propl (ps, NOTLIT (*ps->ttail++));
+ if (ps->conflict) break;
+ }
+#ifndef NADC
+ else if (ps->ttailado < ps->thead)
+ {
+ if (ps->conflict) break;
+ propado (ps, LIT2VAR (*ps->ttailado++));
+ if (ps->conflict) break;
+ }
+#endif
+ else
+ break; /* all assignments propagated, so break */
+ }
+
+ ps->propagations += props;
+}
+
+static unsigned
+drive (PS * ps)
+{
+ unsigned res, vlevel;
+ Lit **p;
+ Var *v;
+
+ res = 0;
+ for (p = ps->added; p < ps->ahead; p++)
+ {
+ v = LIT2VAR (*p);
+ vlevel = v->level;
+ assert (vlevel <= ps->LEVEL);
+ if (vlevel < ps->LEVEL && vlevel > res)
+ res = vlevel;
+ }
+
+ return res;
+}
+
+#ifdef VISCORES
+
+static void
+viscores (PS * ps)
+{
+ Rnk *p, *eor = ps->rnks + ps->max_var;
+ char name[100], cmd[200];
+ FILE * data;
+ Flt s;
+ int i;
+
+ for (p = ps->rnks + 1; p <= ps->eor; p++)
+ {
+ s = p->score;
+ if (s == INFFLT)
+ continue;
+ s = mulflt (s, ps->nvinc);
+ assert (flt2double (s) <= 1.0);
+ }
+
+ sprintf (name, "/tmp/picosat-viscores/data/%08u", ps->conflicts);
+ sprintf (cmd, "sort -n|nl>%s", name);
+
+ data = popen (cmd, "w");
+ for (p = ps->rnks + 1; p <= ps->eor; p++)
+ {
+ s = p->score;
+ if (s == INFFLT)
+ continue;
+ s = mulflt (s, ps->nvinc);
+ fprintf (data, "%lf %d\n", 100.0 * flt2double (s), (int)(p - ps->rnks));
+ }
+ fflush (data);
+ pclose (data);
+
+ for (i = 0; i < 8; i++)
+ {
+ sprintf (cmd, "awk '$3%%8==%d' %s>%s.%d", i, name, name, i);
+ system (cmd);
+ }
+
+ fprintf (ps->fviscores, "set title \"%u\"\n", ps->conflicts);
+ fprintf (ps->fviscores, "plot [0:%u] 0, 100 * (1 - 1/1.1), 100", ps->max_var);
+
+ for (i = 0; i < 8; i++)
+ fprintf (ps->fviscores,
+ ", \"%s.%d\" using 1:2:3 with labels tc lt %d",
+ name, i, i + 1);
+
+ fputc ('\n', ps->fviscores);
+ fflush (ps->fviscores);
+#ifndef WRITEGIF
+ usleep (50000); /* refresh rate of 20 Hz */
+#endif
+}
+
+#endif
+
+static void
+crescore (PS * ps)
+{
+ Cls **p, *c;
+ Act *a;
+ Flt factor;
+ int l = log2flt (ps->cinc);
+ assert (l > 0);
+ factor = base2flt (1, -l);
+
+ for (p = ps->lclauses; p != ps->lhead; p++)
+ {
+ c = *p;
+
+ if (!c)
+ continue;
+
+#ifdef TRACE
+ if (c->collected)
+ continue;
+#endif
+ assert (c->learned);
+
+ if (c->size <= 2)
+ continue;
+
+ a = CLS2ACT (c);
+ *a = mulflt (*a, factor);
+ }
+
+ ps->cinc = mulflt (ps->cinc, factor);
+}
+
+static void
+inc_vinc (PS * ps)
+{
+#ifdef VISCORES
+ ps->nvinc = mulflt (ps->nvinc, ps->fvinc);
+#endif
+ ps->vinc = mulflt (ps->vinc, ps->ifvinc);
+}
+
+inline static void
+inc_max_var (PS * ps)
+{
+ Lit *lit;
+ Rnk *r;
+ Var *v;
+
+ assert (ps->max_var < ps->size_vars);
+
+ if (ps->max_var + 1 == ps->size_vars)
+ enlarge (ps, ps->size_vars + 2*(ps->size_vars + 3) / 4); /* +25% */
+
+ ps->max_var++; /* new index of variable */
+ assert (ps->max_var); /* no unsigned overflow */
+
+ assert (ps->max_var < ps->size_vars);
+
+ lit = ps->lits + 2 * ps->max_var;
+ lit[0].val = lit[1].val = UNDEF;
+
+ memset (ps->htps + 2 * ps->max_var, 0, 2 * sizeof *ps->htps);
+#ifndef NDSC
+ memset (ps->dhtps + 2 * ps->max_var, 0, 2 * sizeof *ps->dhtps);
+#endif
+ memset (ps->impls + 2 * ps->max_var, 0, 2 * sizeof *ps->impls);
+ memset (ps->jwh + 2 * ps->max_var, 0, 2 * sizeof *ps->jwh);
+
+ v = ps->vars + ps->max_var; /* initialize variable components */
+ CLR (v);
+
+ r = ps->rnks + ps->max_var; /* initialize rank */
+ CLR (r);
+
+ hpush (ps, r);
+}
+
+static void
+force (PS * ps, Cls * c)
+{
+ Lit ** p, ** eol, * lit, * forced;
+ Cls * reason;
+
+ forced = 0;
+ reason = c;
+
+ eol = end_of_lits (c);
+ for (p = c->lits; p < eol; p++)
+ {
+ lit = *p;
+ if (lit->val == UNDEF)
+ {
+ assert (!forced);
+ forced = lit;
+#ifdef NO_BINARY_CLAUSES
+ if (c == &ps->impl)
+ reason = LIT2REASON (NOTLIT (p[p == c->lits ? 1 : -1]));
+#endif
+ }
+ else
+ assert (lit->val == FALSE);
+ }
+
+#ifdef NO_BINARY_CLAUSES
+ if (c == &ps->impl)
+ resetimpl (ps);
+#endif
+ if (!forced)
+ return;
+
+ assign_forced (ps, forced, reason);
+}
+
+static void
+inc_lreduce (PS * ps)
+{
+#ifdef STATS
+ ps->inclreduces++;
+#endif
+ ps->lreduce *= FREDUCE;
+ ps->lreduce /= 100;
+ report (ps, 1, '+');
+}
+
+static void
+backtrack (PS * ps)
+{
+ unsigned new_level;
+ Cls * c;
+
+ ps->conflicts++;
+ LOG ( fprintf (ps->out, "%sconflict ", ps->prefix); dumpclsnl (ps, ps->conflict));
+
+ analyze (ps);
+ new_level = drive (ps);
+ // TODO: why not? assert (new_level != 1 || (ps->ahead - ps->added) == 2);
+ c = add_simplified_clause (ps, 1);
+ undo (ps, new_level);
+ force (ps, c);
+
+ if (
+#ifndef NFL
+ !ps->simplifying &&
+#endif
+ !--ps->lreduceadjustcnt)
+ {
+ /* With FREDUCE==110 and FREDADJ=121 we stir 'lreduce' to be
+ * proportional to 'sqrt(conflicts)'. In earlier version we actually
+ * used 'FREDADJ=150', which results in 'lreduce' to approximate
+ * 'conflicts^(log(1.1)/log(1.5))' which is close to the fourth root
+ * of 'conflicts', since log(1.1)/log(1.5)=0.235 (as observed by
+ * Donald Knuth). The square root is the same we get by a Glucose
+ * style increase, which simply adds a constant at every reduction.
+ * This would be way simpler to implement but for now we keep the more
+ * complicated code using the adjust increments and counters.
+ */
+ ps->lreduceadjustinc *= FREDADJ; ps->lreduceadjustinc /= 100; ps->lreduceadjustcnt
+ = ps->lreduceadjustinc;
+ inc_lreduce (ps);
+ }
+
+ if (ps->verbosity >= 4 && !(ps->conflicts % 1000))
+ report (ps, 4, 'C');
+}
+
+static void
+inc_cinc (PS * ps)
+{
+ ps->cinc = mulflt (ps->cinc, ps->fcinc);
+ if (ps->lcinc < ps->cinc)
+ crescore (ps);
+}
+
+static void
+incincs (PS * ps)
+{
+ inc_vinc (ps);
+ inc_cinc (ps);
+#ifdef VISCORES
+ viscores (ps);
+#endif
+}
+
+static void
+disconnect_clause (PS * ps, Cls * c)
+{
+ assert (c->connected);
+
+ if (c->size > 2)
+ {
+ if (c->learned)
+ {
+ assert (ps->nlclauses > 0);
+ ps->nlclauses--;
+
+ assert (ps->llits >= c->size);
+ ps->llits -= c->size;
+ }
+ else
+ {
+ assert (ps->noclauses > 0);
+ ps->noclauses--;
+
+ assert (ps->olits >= c->size);
+ ps->olits -= c->size;
+ }
+ }
+
+#ifndef NDEBUG
+ c->connected = 0;
+#endif
+}
+
+static int
+clause_is_toplevel_satisfied (PS * ps, Cls * c)
+{
+ Lit *lit, **p, **eol = end_of_lits (c);
+ Var *v;
+
+ for (p = c->lits; p < eol; p++)
+ {
+ lit = *p;
+ if (lit->val == TRUE)
+ {
+ v = LIT2VAR (lit);
+ if (!v->level)
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+static int
+collect_clause (PS * ps, Cls * c)
+{
+ assert (c->collect);
+ c->collect = 0;
+
+#ifdef TRACE
+ assert (!c->collected);
+ c->collected = 1;
+#endif
+ disconnect_clause (ps, c);
+
+#ifdef TRACE
+ if (ps->trace && (!c->learned || c->used))
+ return 0;
+#endif
+ delete_clause (ps, c);
+
+ return 1;
+}
+
+static size_t
+collect_clauses (PS * ps)
+{
+ Cls *c, **p, **q, * next;
+ Lit * lit, * eol;
+ size_t res;
+ int i;
+
+ res = ps->current_bytes;
+
+ eol = ps->lits + 2 * ps->max_var + 1;
+ for (lit = ps->lits + 2; lit <= eol; lit++)
+ {
+ for (i = 0; i <= 1; i++)
+ {
+ if (i)
+ {
+#ifdef NO_BINARY_CLAUSES
+ Ltk * lstk = LIT2IMPLS (lit);
+ Lit ** r, ** s;
+ r = lstk->start;
+ if (lit->val != TRUE || LIT2VAR (lit)->level)
+ for (s = r; s < lstk->start + lstk->count; s++)
+ {
+ Lit * other = *s;
+ Var *v = LIT2VAR (other);
+ if (v->level ||
+ other->val != TRUE)
+ *r++ = other;
+ }
+ lstk->count = r - lstk->start;
+ continue;
+#else
+ p = LIT2IMPLS (lit);
+#endif
+ }
+ else
+ p = LIT2HTPS (lit);
+
+ for (c = *p; c; c = next)
+ {
+ q = c->next;
+ if (c->lits[0] != lit)
+ q++;
+
+ next = *q;
+ if (c->collect)
+ *p = next;
+ else
+ p = q;
+ }
+ }
+ }
+
+#ifndef NDSC
+ for (lit = ps->lits + 2; lit <= eol; lit++)
+ {
+ p = LIT2DHTPS (lit);
+ while ((c = *p))
+ {
+ Lit * other = c->lits[0];
+ if (other == lit)
+ {
+ q = c->next + 1;
+ }
+ else
+ {
+ assert (c->lits[1] == lit);
+ q = c->next;
+ }
+
+ if (c->collect)
+ *p = *q;
+ else
+ p = q;
+ }
+ }
+#endif
+
+ for (p = SOC; p != EOC; p = NXC (p))
+ {
+ c = *p;
+
+ if (!c)
+ continue;
+
+ if (!c->collect)
+ continue;
+
+ if (collect_clause (ps, c))
+ *p = 0;
+ }
+
+#ifdef TRACE
+ if (!ps->trace)
+#endif
+ {
+ q = ps->oclauses;
+ for (p = q; p < ps->ohead; p++)
+ if ((c = *p))
+ *q++ = c;
+ ps->ohead = q;
+
+ q = ps->lclauses;
+ for (p = q; p < ps->lhead; p++)
+ if ((c = *p))
+ *q++ = c;
+ ps->lhead = q;
+ }
+
+ assert (ps->current_bytes <= res);
+ res -= ps->current_bytes;
+ ps->recycled += res;
+
+ LOG ( fprintf (ps->out, "%scollected %ld bytes\n", ps->prefix, (long)res));
+
+ return res;
+}
+
+static int
+need_to_reduce (PS * ps)
+{
+ return ps->nlclauses >= reduce_limit_on_lclauses (ps);
+}
+
+#ifdef NLUBY
+
+static void
+inc_drestart (PS * ps)
+{
+ ps->drestart *= FRESTART;
+ ps->drestart /= 100;
+
+ if (ps->drestart >= MAXRESTART)
+ ps->drestart = MAXRESTART;
+}
+
+static void
+inc_ddrestart (PS * ps)
+{
+ ps->ddrestart *= FRESTART;
+ ps->ddrestart /= 100;
+
+ if (ps->ddrestart >= MAXRESTART)
+ ps->ddrestart = MAXRESTART;
+}
+
+#else
+
+static unsigned
+luby (unsigned i)
+{
+ unsigned k;
+ for (k = 1; k < 32; k++)
+ if (i == (1u << k) - 1)
+ return 1u << (k - 1);
+
+ for (k = 1;; k++)
+ if ((1u << (k - 1)) <= i && i < (1u << k) - 1)
+ return luby (i - (1u << (k-1)) + 1);
+}
+
+#endif
+
+#ifndef NLUBY
+static void
+inc_lrestart (PS * ps, int skip)
+{
+ unsigned delta;
+
+ delta = 100 * luby (++ps->lubycnt);
+ ps->lrestart = ps->conflicts + delta;
+
+ if (ps->waslubymaxdelta)
+ report (ps, 1, skip ? 'N' : 'R');
+ else
+ report (ps, 2, skip ? 'n' : 'r');
+
+ if (delta > ps->lubymaxdelta)
+ {
+ ps->lubymaxdelta = delta;
+ ps->waslubymaxdelta = 1;
+ }
+ else
+ ps->waslubymaxdelta = 0;
+}
+#endif
+
+static void
+init_restart (PS * ps)
+{
+#ifdef NLUBY
+ /* TODO: why is it better in incremental usage to have smaller initial
+ * outer restart interval?
+ */
+ ps->ddrestart = ps->calls > 1 ? MINRESTART : 1000;
+ ps->drestart = MINRESTART;
+ ps->lrestart = ps->conflicts + ps->drestart;
+#else
+ ps->lubycnt = 0;
+ ps->lubymaxdelta = 0;
+ ps->waslubymaxdelta = 0;
+ inc_lrestart (ps, 0);
+#endif
+}
+
+static void
+restart (PS * ps)
+{
+ int skip;
+#ifdef NLUBY
+ char kind;
+ int outer;
+
+ inc_drestart (ps);
+ outer = (ps->drestart >= ps->ddrestart);
+
+ if (outer)
+ skip = very_high_agility (ps);
+ else
+ skip = high_agility (ps);
+#else
+ skip = medium_agility (ps);
+#endif
+
+#ifdef STATS
+ if (skip)
+ ps->skippedrestarts++;
+#endif
+
+ assert (ps->conflicts >= ps->lrestart);
+
+ if (!skip)
+ {
+ ps->restarts++;
+ assert (ps->LEVEL > 1);
+ LOG ( fprintf (ps->out, "%srestart %u\n", ps->prefix, ps->restarts));
+ undo (ps, 0);
+ }
+
+#ifdef NLUBY
+ if (outer)
+ {
+ kind = skip ? 'N' : 'R';
+ inc_ddrestart (ps);
+ ps->drestart = MINRESTART;
+ }
+ else if (skip)
+ {
+ kind = 'n';
+ }
+ else
+ {
+ kind = 'r';
+ }
+
+ assert (ps->drestart <= MAXRESTART);
+ ps->lrestart = ps->conflicts + ps->drestart;
+ assert (ps->lrestart > ps->conflicts);
+
+ report (outer ? 1 : 2, kind);
+#else
+ inc_lrestart (ps, skip);
+#endif
+}
+
+inline static void
+assign_decision (PS * ps, Lit * lit)
+{
+ assert (!ps->conflict);
+
+ ps->LEVEL++;
+
+ LOG ( fprintf (ps->out, "%snew level %u\n", ps->prefix, ps->LEVEL));
+ LOG ( fprintf (ps->out,
+ "%sassign %d at level %d <= DECISION\n",
+ ps->prefix, LIT2INT (lit), ps->LEVEL));
+
+ assign (ps, lit, 0);
+}
+
+#ifndef NFL
+
+static int
+lit_has_binary_clauses (PS * ps, Lit * lit)
+{
+#ifdef NO_BINARY_CLAUSES
+ Ltk* lstk = LIT2IMPLS (lit);
+ return lstk->count != 0;
+#else
+ return *LIT2IMPLS (lit) != 0;
+#endif
+}
+
+static void
+flbcp (PS * ps)
+{
+#ifdef STATS
+ unsigned long long propagaions_before_bcp = ps->propagations;
+#endif
+ bcp (ps);
+#ifdef STATS
+ ps->flprops += ps->propagations - propagaions_before_bcp;
+#endif
+}
+
+inline static int
+cmp_inverse_rnk (PS * ps, Rnk * a, Rnk * b)
+{
+ (void) ps;
+ return -cmp_rnk (a, b);
+}
+
+inline static Flt
+rnk2jwh (PS * ps, Rnk * r)
+{
+ Flt res, sum, pjwh, njwh;
+ Lit * plit, * nlit;
+
+ plit = RNK2LIT (r);
+ nlit = plit + 1;
+
+ pjwh = *LIT2JWH (plit);
+ njwh = *LIT2JWH (nlit);
+
+ res = mulflt (pjwh, njwh);
+
+ sum = addflt (pjwh, njwh);
+ sum = mulflt (sum, base2flt (1, -10));
+ res = addflt (res, sum);
+
+ return res;
+}
+
+static int
+cmp_inverse_jwh_rnk (PS * ps, Rnk * r, Rnk * s)
+{
+ Flt a = rnk2jwh (ps, r);
+ Flt b = rnk2jwh (ps, s);
+ int res = cmpflt (a, b);
+
+ if (res)
+ return -res;
+
+ return cmp_inverse_rnk (ps, r, s);
+}
+
+static void
+faillits (PS * ps)
+{
+ unsigned i, j, old_trail_count, common, saved_count;
+ unsigned new_saved_size, oldladded = ps->ladded;
+ unsigned long long limit, delta;
+ Lit * lit, * other, * pivot;
+ Rnk * r, ** p, ** q;
+ int new_trail_count;
+ double started;
+
+ if (ps->plain)
+ return;
+
+ if (ps->heap + 1 >= ps->hhead)
+ return;
+
+ if (ps->propagations < ps->fllimit)
+ return;
+
+ sflush (ps);
+ started = ps->seconds;
+
+ ps->flcalls++;
+#ifdef STATSA
+ ps->flrounds++;
+#endif
+ delta = ps->propagations/10;
+ if (delta >= 100*1000*1000) delta = 100*1000*1000;
+ else if (delta <= 100*1000) delta = 100*1000;
+
+ limit = ps->propagations + delta;
+ ps->fllimit = ps->propagations;
+
+ assert (!ps->LEVEL);
+ assert (ps->simplifying);
+
+ if (ps->flcalls <= 1)
+ SORT (Rnk *, cmp_inverse_jwh_rnk, ps->heap + 1, ps->hhead - (ps->heap + 1));
+ else
+ SORT (Rnk *, cmp_inverse_rnk, ps->heap + 1, ps->hhead - (ps->heap + 1));
+
+ i = 1; /* NOTE: heap starts at position '1' */
+
+ while (ps->propagations < limit)
+ {
+ if (ps->heap + i == ps->hhead)
+ {
+ if (ps->ladded == oldladded)
+ break;
+
+ i = 1;
+#ifdef STATS
+ ps->flrounds++;
+#endif
+ oldladded = ps->ladded;
+ }
+
+ assert (ps->heap + i < ps->hhead);
+
+ r = ps->heap[i++];
+ lit = RNK2LIT (r);
+
+ if (lit->val)
+ continue;
+
+ if (!lit_has_binary_clauses (ps, NOTLIT (lit)))
+ {
+#ifdef STATS
+ ps->flskipped++;
+#endif
+ continue;
+ }
+
+#ifdef STATS
+ ps->fltried++;
+#endif
+ LOG ( fprintf (ps->out, "%strying %d as failed literal\n",
+ ps->prefix, LIT2INT (lit)));
+
+ assign_decision (ps, lit);
+ old_trail_count = ps->thead - ps->trail;
+ flbcp (ps);
+
+ if (ps->conflict)
+ {
+EXPLICITLY_FAILED_LITERAL:
+ LOG ( fprintf (ps->out, "%sfound explicitly failed literal %d\n",
+ ps->prefix, LIT2INT (lit)));
+
+ ps->failedlits++;
+ ps->efailedlits++;
+
+ backtrack (ps);
+ flbcp (ps);
+
+ if (!ps->conflict)
+ continue;
+
+CONTRADICTION:
+ assert (!ps->LEVEL);
+ backtrack (ps);
+ assert (ps->mtcls);
+
+ goto RETURN;
+ }
+
+ if (ps->propagations >= limit)
+ {
+ undo (ps, 0);
+ break;
+ }
+
+ lit = NOTLIT (lit);
+
+ if (!lit_has_binary_clauses (ps, NOTLIT (lit)))
+ {
+#ifdef STATS
+ ps->flskipped++;
+#endif
+ undo (ps, 0);
+ continue;
+ }
+
+#ifdef STATS
+ ps->fltried++;
+#endif
+ LOG ( fprintf (ps->out, "%strying %d as failed literals\n",
+ ps->prefix, LIT2INT (lit)));
+
+ new_trail_count = ps->thead - ps->trail;
+ saved_count = new_trail_count - old_trail_count;
+
+ if (saved_count > ps->saved_size)
+ {
+ new_saved_size = ps->saved_size ? 2 * ps->saved_size : 1;
+ while (saved_count > new_saved_size)
+ new_saved_size *= 2;
+
+ RESIZEN (ps->saved, ps->saved_size, new_saved_size);
+ ps->saved_size = new_saved_size;
+ }
+
+ for (j = 0; j < saved_count; j++)
+ ps->saved[j] = ps->trail[old_trail_count + j];
+
+ undo (ps, 0);
+
+ assign_decision (ps, lit);
+ flbcp (ps);
+
+ if (ps->conflict)
+ goto EXPLICITLY_FAILED_LITERAL;
+
+ pivot = (ps->thead - ps->trail <= new_trail_count) ? lit : NOTLIT (lit);
+
+ common = 0;
+ for (j = 0; j < saved_count; j++)
+ if ((other = ps->saved[j])->val == TRUE)
+ ps->saved[common++] = other;
+
+ undo (ps, 0);
+
+ LOG (if (common)
+ fprintf (ps->out,
+ "%sfound %d literals implied by %d and %d\n",
+ ps->prefix, common,
+ LIT2INT (NOTLIT (lit)), LIT2INT (lit)));
+
+#if 1 // set to zero to disable 'lifting'
+ for (j = 0;
+ j < common
+ /* TODO: For some Velev benchmarks, extracting the common implicit
+ * failed literals took quite some time. This needs to be fixed by
+ * a dedicated analyzer. Up to then we bound the number of
+ * propagations in this loop as well.
+ */
+ && ps->propagations < limit + delta
+ ; j++)
+ {
+ other = ps->saved[j];
+
+ if (other->val == TRUE)
+ continue;
+
+ assert (!other->val);
+
+ LOG ( fprintf (ps->out,
+ "%sforcing %d as forced implicitly failed literal\n",
+ ps->prefix, LIT2INT (other)));
+
+ assert (pivot != NOTLIT (other));
+ assert (pivot != other);
+
+ assign_decision (ps, NOTLIT (other));
+ flbcp (ps);
+
+ assert (ps->LEVEL == 1);
+
+ if (ps->conflict)
+ {
+ backtrack (ps);
+ assert (!ps->LEVEL);
+ }
+ else
+ {
+ assign_decision (ps, pivot);
+ flbcp (ps);
+
+ backtrack (ps);
+
+ if (ps->LEVEL)
+ {
+ assert (ps->LEVEL == 1);
+
+ flbcp (ps);
+
+ if (ps->conflict)
+ {
+ backtrack (ps);
+ assert (!ps->LEVEL);
+ }
+ else
+ {
+ assign_decision (ps, NOTLIT (pivot));
+ flbcp (ps);
+ backtrack (ps);
+
+ if (ps->LEVEL)
+ {
+ assert (ps->LEVEL == 1);
+ flbcp (ps);
+
+ if (!ps->conflict)
+ {
+#ifdef STATS
+ ps->floopsed++;
+#endif
+ undo (ps, 0);
+ continue;
+ }
+
+ backtrack (ps);
+ }
+
+ assert (!ps->LEVEL);
+ }
+
+ assert (!ps->LEVEL);
+ }
+ }
+ assert (!ps->LEVEL);
+ flbcp (ps);
+
+ ps->failedlits++;
+ ps->ifailedlits++;
+
+ if (ps->conflict)
+ goto CONTRADICTION;
+ }
+#endif
+ }
+
+ ps->fllimit += 9 * (ps->propagations - ps->fllimit); /* 10% for failed literals */
+
+RETURN:
+
+ /* First flush top level assigned literals. Those are prohibited from
+ * being pushed up the heap during 'faillits' since 'simplifying' is set.
+ */
+ assert (ps->heap < ps->hhead);
+ for (p = q = ps->heap + 1; p < ps->hhead; p++)
+ {
+ r = *p;
+ lit = RNK2LIT (r);
+ if (lit->val)
+ r->pos = 0;
+ else
+ *q++ = r;
+ }
+
+ /* Then resort with respect to EVSIDS score and fix positions.
+ */
+ SORT (Rnk *, cmp_inverse_rnk, ps->heap + 1, ps->hhead - (ps->heap + 1));
+ for (p = ps->heap + 1; p < ps->hhead; p++)
+ (*p)->pos = p - ps->heap;
+
+ sflush (ps);
+ ps->flseconds += ps->seconds - started;
+}
+
+#endif
+
+static void
+simplify (PS * ps, int forced)
+{
+ Lit * lit, * notlit, ** t;
+ unsigned collect, delta;
+#ifdef STATS
+ size_t bytes_collected;
+#endif
+ int * q, ilit;
+ Cls **p, *c;
+ Var * v;
+
+#ifndef NDEDBUG
+ (void) forced;
+#endif
+
+ assert (!ps->mtcls);
+ assert (!satisfied (ps));
+ assert (forced || ps->lsimplify <= ps->propagations);
+ assert (forced || ps->fsimplify <= ps->fixed);
+
+ if (ps->LEVEL)
+ undo (ps, 0);
+#ifndef NFL
+ ps->simplifying = 1;
+ faillits (ps);
+ ps->simplifying = 0;
+
+ if (ps->mtcls)
+ return;
+#endif
+
+ if (ps->cils != ps->cilshead)
+ {
+ assert (ps->ttail == ps->thead);
+ assert (ps->ttail2 == ps->thead);
+ ps->ttail = ps->trail;
+ for (t = ps->trail; t < ps->thead; t++)
+ {
+ lit = *t;
+ v = LIT2VAR (lit);
+ if (v->internal)
+ {
+ assert (LIT2INT (lit) < 0);
+ assert (lit->val == TRUE);
+ unassign (ps, lit);
+ }
+ else
+ *ps->ttail++ = lit;
+ }
+ ps->ttail2 = ps->thead = ps->ttail;
+
+ for (q = ps->cils; q != ps->cilshead; q++)
+ {
+ ilit = *q;
+ assert (0 < ilit && ilit <= (int) ps->max_var);
+ v = ps->vars + ilit;
+ assert (v->internal);
+ v->level = 0;
+ v->reason = 0;
+ lit = int2lit (ps, -ilit);
+ assert (lit->val == UNDEF);
+ lit->val = TRUE;
+ notlit = NOTLIT (lit);
+ assert (notlit->val == UNDEF);
+ notlit->val = FALSE;
+ }
+ }
+
+ collect = 0;
+ for (p = SOC; p != EOC; p = NXC (p))
+ {
+ c = *p;
+ if (!c)
+ continue;
+
+#ifdef TRACE
+ if (c->collected)
+ continue;
+#endif
+
+ if (c->locked)
+ continue;
+
+ assert (!c->collect);
+ if (clause_is_toplevel_satisfied (ps, c))
+ {
+ mark_clause_to_be_collected (c);
+ collect++;
+ }
+ }
+
+ LOG ( fprintf (ps->out, "%scollecting %d clauses\n", ps->prefix, collect));
+#ifdef STATS
+ bytes_collected =
+#endif
+ collect_clauses (ps);
+#ifdef STATS
+ ps->srecycled += bytes_collected;
+#endif
+
+ if (ps->cils != ps->cilshead)
+ {
+ for (q = ps->cils; q != ps->cilshead; q++)
+ {
+ ilit = *q;
+ assert (0 < ilit && ilit <= (int) ps->max_var);
+ assert (ps->vars[ilit].internal);
+ if (ps->rilshead == ps->eorils)
+ ENLARGE (ps->rils, ps->rilshead, ps->eorils);
+ *ps->rilshead++ = ilit;
+ lit = int2lit (ps, -ilit);
+ assert (lit->val == TRUE);
+ lit->val = UNDEF;
+ notlit = NOTLIT (lit);
+ assert (notlit->val == FALSE);
+ notlit->val = UNDEF;
+ }
+ ps->cilshead = ps->cils;
+ }
+
+ delta = 10 * (ps->olits + ps->llits) + 100000;
+ if (delta > 2000000)
+ delta = 2000000;
+ ps->lsimplify = ps->propagations + delta;
+ ps->fsimplify = ps->fixed;
+ ps->simps++;
+
+ report (ps, 1, 's');
+}
+
+static void
+iteration (PS * ps)
+{
+ assert (!ps->LEVEL);
+ assert (bcp_queue_is_empty (ps));
+ assert (ps->isimplify < ps->fixed);
+
+ ps->iterations++;
+ report (ps, 2, 'i');
+#ifdef NLUBY
+ ps->drestart = MINRESTART;
+ ps->lrestart = ps->conflicts + ps->drestart;
+#else
+ init_restart (ps);
+#endif
+ ps->isimplify = ps->fixed;
+}
+
+static int
+cmp_glue_activity_size (PS * ps, Cls * c, Cls * d)
+{
+ Act a, b, * p, * q;
+
+ (void) ps;
+
+ assert (c->learned);
+ assert (d->learned);
+
+ if (c->glue < d->glue) // smaller glue preferred
+ return 1;
+
+ if (c->glue > d->glue)
+ return -1;
+
+ p = CLS2ACT (c);
+ q = CLS2ACT (d);
+ a = *p;
+ b = *q;
+
+ if (a < b) // then higher activity
+ return -1;
+
+ if (b < a)
+ return 1;
+
+ if (c->size < d->size) // then smaller size
+ return 1;
+
+ if (c->size > d->size)
+ return -1;
+
+ return 0;
+}
+
+static void
+reduce (PS * ps, unsigned percentage)
+{
+ unsigned redcount, lcollect, collect, target;
+#ifdef STATS
+ size_t bytes_collected;
+#endif
+ Cls **p, *c;
+
+ assert (ps->rhead == ps->resolved);
+
+ ps->lastreduceconflicts = ps->conflicts;
+
+ assert (percentage <= 100);
+ LOG ( fprintf (ps->out,
+ "%sreducing %u%% learned clauses\n",
+ ps->prefix, percentage));
+
+ while (ps->nlclauses - ps->llocked > (unsigned)(ps->eor - ps->resolved))
+ ENLARGE (ps->resolved, ps->rhead, ps->eor);
+
+ collect = 0;
+ lcollect = 0;
+
+ for (p = ((ps->fsimplify < ps->fixed) ? SOC : ps->lclauses); p != EOC; p = NXC (p))
+ {
+ c = *p;
+ if (!c)
+ continue;
+
+#ifdef TRACE
+ if (c->collected)
+ continue;
+#endif
+
+ if (c->locked)
+ continue;
+
+ assert (!c->collect);
+ if (ps->fsimplify < ps->fixed && clause_is_toplevel_satisfied (ps, c))
+ {
+ mark_clause_to_be_collected (c);
+ collect++;
+
+ if (c->learned && c->size > 2)
+ lcollect++;
+
+ continue;
+ }
+
+ if (!c->learned)
+ continue;
+
+ if (c->size <= 2)
+ continue;
+
+ assert (ps->rhead < ps->eor);
+ *ps->rhead++ = c;
+ }
+ assert (ps->rhead <= ps->eor);
+
+ ps->fsimplify = ps->fixed;
+
+ redcount = ps->rhead - ps->resolved;
+ SORT (Cls *, cmp_glue_activity_size, ps->resolved, redcount);
+
+ assert (ps->nlclauses >= lcollect);
+ target = ps->nlclauses - lcollect + 1;
+
+ target = (percentage * target + 99) / 100;
+
+ if (target >= redcount)
+ target = redcount;
+
+ ps->rhead = ps->resolved + target;
+ while (ps->rhead > ps->resolved)
+ {
+ c = *--ps->rhead;
+ mark_clause_to_be_collected (c);
+
+ collect++;
+ if (c->learned && c->size > 2) /* just for consistency */
+ lcollect++;
+ }
+
+ if (collect)
+ {
+ ps->reductions++;
+#ifdef STATS
+ bytes_collected =
+#endif
+ collect_clauses (ps);
+#ifdef STATS
+ ps->rrecycled += bytes_collected;
+#endif
+ report (ps, 2, '-');
+ }
+
+ if (!lcollect)
+ inc_lreduce (ps); /* avoid dead lock */
+
+ assert (ps->rhead == ps->resolved);
+}
+
+static void
+init_reduce (PS * ps)
+{
+ // lreduce = loadded / 2;
+ ps->lreduce = 1000;
+
+ if (ps->lreduce < 100)
+ ps->lreduce = 100;
+
+ if (ps->verbosity)
+ fprintf (ps->out,
+ "%s\n%sinitial reduction limit %u clauses\n%s\n",
+ ps->prefix, ps->prefix, ps->lreduce, ps->prefix);
+}
+
+static unsigned
+rng (PS * ps)
+{
+ unsigned res = ps->srng;
+ ps->srng *= 1664525u;
+ ps->srng += 1013904223u;
+ NOLOG ( fprintf (ps->out, "%srng () = %u\n", ps->prefix, res));
+ return res;
+}
+
+static unsigned
+rrng (PS * ps, unsigned low, unsigned high)
+{
+ unsigned long long tmp;
+ unsigned res, elements;
+ assert (low <= high);
+ elements = high - low + 1;
+ tmp = rng (ps);
+ tmp *= elements;
+ tmp >>= 32;
+ tmp += low;
+ res = tmp;
+ NOLOG ( fprintf (ps->out, "%srrng (ps, %u, %u) = %u\n", ps->prefix, low, high, res));
+ assert (low <= res);
+ assert (res <= high);
+ return res;
+}
+
+static Lit *
+decide_phase (PS * ps, Lit * lit)
+{
+ Lit * not_lit = NOTLIT (lit);
+ Var *v = LIT2VAR (lit);
+
+ assert (LIT2SGN (lit) > 0);
+ if (v->usedefphase)
+ {
+ if (v->defphase)
+ {
+ /* assign to TRUE */
+ }
+ else
+ {
+ /* assign to FALSE */
+ lit = not_lit;
+ }
+ }
+ else if (!v->assigned)
+ {
+#ifdef STATS
+ ps->staticphasedecisions++;
+#endif
+ if (ps->defaultphase == POSPHASE)
+ {
+ /* assign to TRUE */
+ }
+ else if (ps->defaultphase == NEGPHASE)
+ {
+ /* assign to FALSE */
+ lit = not_lit;
+ }
+ else if (ps->defaultphase == RNDPHASE)
+ {
+ /* randomly assign default phase */
+ if (rrng (ps, 1, 2) != 2)
+ lit = not_lit;
+ }
+ else if (*LIT2JWH(lit) <= *LIT2JWH (not_lit))
+ {
+ /* assign to FALSE (Jeroslow-Wang says there are more short
+ * clauses with negative occurence of this variable, so satisfy
+ * those, to minimize BCP)
+ */
+ lit = not_lit;
+ }
+ else
+ {
+ /* assign to TRUE (... but strictly more positive occurrences) */
+ }
+ }
+ else
+ {
+ /* repeat last phase: phase saving heuristic */
+
+ if (v->phase)
+ {
+ /* assign to TRUE (last phase was TRUE as well) */
+ }
+ else
+ {
+ /* assign to FALSE (last phase was FALSE as well) */
+ lit = not_lit;
+ }
+ }
+
+ return lit;
+}
+
+static unsigned
+gcd (unsigned a, unsigned b)
+{
+ unsigned tmp;
+
+ assert (a);
+ assert (b);
+
+ if (a < b)
+ {
+ tmp = a;
+ a = b;
+ b = tmp;
+ }
+
+ while (b)
+ {
+ assert (a >= b);
+ tmp = b;
+ b = a % b;
+ a = tmp;
+ }
+
+ return a;
+}
+
+static Lit *
+rdecide (PS * ps)
+{
+ unsigned idx, delta, spread;
+ Lit * res;
+
+ spread = RDECIDE;
+ if (rrng (ps, 1, spread) != 2)
+ return 0;
+
+ assert (1 <= ps->max_var);
+ idx = rrng (ps, 1, ps->max_var);
+ res = int2lit (ps, idx);
+
+ if (res->val != UNDEF)
+ {
+ delta = rrng (ps, 1, ps->max_var);
+ while (gcd (delta, ps->max_var) != 1)
+ delta--;
+
+ assert (1 <= delta);
+ assert (delta <= ps->max_var);
+
+ do {
+ idx += delta;
+ if (idx > ps->max_var)
+ idx -= ps->max_var;
+ res = int2lit (ps, idx);
+ } while (res->val != UNDEF);
+ }
+
+#ifdef STATS
+ ps->rdecisions++;
+#endif
+ res = decide_phase (ps, res);
+ LOG ( fprintf (ps->out, "%srdecide %d\n", ps->prefix, LIT2INT (res)));
+
+ return res;
+}
+
+static Lit *
+sdecide (PS * ps)
+{
+ Lit *res;
+ Rnk *r;
+
+ for (;;)
+ {
+ r = htop (ps);
+ res = RNK2LIT (r);
+ if (res->val == UNDEF) break;
+ (void) hpop (ps);
+ NOLOG ( fprintf (ps->out,
+ "%shpop %u %u %u\n",
+ ps->prefix, r - ps->rnks,
+ FLTMANTISSA(r->score),
+ FLTEXPONENT(r->score)));
+ }
+
+#ifdef STATS
+ ps->sdecisions++;
+#endif
+ res = decide_phase (ps, res);
+
+ LOG ( fprintf (ps->out, "%ssdecide %d\n", ps->prefix, LIT2INT (res)));
+
+ return res;
+}
+
+static Lit *
+adecide (PS * ps)
+{
+ Lit *lit;
+ Var * v;
+
+ assert (ps->als < ps->alshead);
+ assert (!ps->failed_assumption);
+
+ while (ps->alstail < ps->alshead)
+ {
+ lit = *ps->alstail++;
+
+ if (lit->val == FALSE)
+ {
+ ps->failed_assumption = lit;
+ v = LIT2VAR (lit);
+
+ use_var (ps, v);
+
+ LOG ( fprintf (ps->out, "%sfirst failed assumption %d\n",
+ ps->prefix, LIT2INT (ps->failed_assumption)));
+ fanalyze (ps);
+ return 0;
+ }
+
+ if (lit->val == TRUE)
+ {
+ v = LIT2VAR (lit);
+ if (v->level > ps->adecidelevel)
+ ps->adecidelevel = v->level;
+ continue;
+ }
+
+#ifdef STATS
+ ps->assumptions++;
+#endif
+ LOG ( fprintf (ps->out, "%sadecide %d\n", ps->prefix, LIT2INT (lit)));
+ ps->adecidelevel = ps->LEVEL + 1;
+
+ return lit;
+ }
+
+ return 0;
+}
+
+static void
+decide (PS * ps)
+{
+ Lit * lit;
+
+ assert (!satisfied (ps));
+ assert (!ps->conflict);
+
+ if (ps->alstail < ps->alshead && (lit = adecide (ps)))
+ ;
+ else if (ps->failed_assumption)
+ return;
+ else if (satisfied (ps))
+ return;
+ else if (!(lit = rdecide (ps)))
+ lit = sdecide (ps);
+
+ assert (lit);
+ assign_decision (ps, lit);
+
+ ps->levelsum += ps->LEVEL;
+ ps->decisions++;
+}
+
+static int
+sat (PS * ps, int l)
+{
+ int count = 0, backtracked;
+
+ if (!ps->conflict)
+ bcp (ps);
+
+ if (ps->conflict)
+ backtrack (ps);
+
+ if (ps->mtcls)
+ return PICOSAT_UNSATISFIABLE;
+
+ if (satisfied (ps))
+ goto SATISFIED;
+
+ if (ps->lsimplify <= ps->propagations)
+ simplify (ps, 0);
+
+ if (ps->mtcls)
+ return PICOSAT_UNSATISFIABLE;
+
+ if (satisfied (ps))
+ goto SATISFIED;
+
+ init_restart (ps);
+
+ if (!ps->lreduce)
+ init_reduce (ps);
+
+ ps->isimplify = ps->fixed;
+ backtracked = 0;
+
+ for (;;)
+ {
+ if (!ps->conflict)
+ bcp (ps);
+
+ if (ps->conflict)
+ {
+ incincs (ps);
+ backtrack (ps);
+
+ if (ps->mtcls)
+ return PICOSAT_UNSATISFIABLE;
+ backtracked = 1;
+ continue;
+ }
+
+ if (satisfied (ps))
+ {
+SATISFIED:
+#ifndef NDEBUG
+ original_clauses_satisfied (ps);
+ assumptions_satisfied (ps);
+#endif
+ return PICOSAT_SATISFIABLE;
+ }
+
+ if (backtracked)
+ {
+ backtracked = 0;
+ if (!ps->LEVEL && ps->isimplify < ps->fixed)
+ iteration (ps);
+ }
+
+ if (l >= 0 && count >= l) /* decision limit reached ? */
+ return PICOSAT_UNKNOWN;
+
+ if (ps->interrupt.function && /* external interrupt */
+ count > 0 && !(count % INTERRUPTLIM) &&
+ ps->interrupt.function (ps->interrupt.state))
+ return PICOSAT_UNKNOWN;
+
+ if (ps->propagations >= ps->lpropagations)/* propagation limit reached ? */
+ return PICOSAT_UNKNOWN;
+
+#ifndef NADC
+ if (!ps->adodisabled && ps->adoconflicts >= ps->adoconflictlimit)
+ {
+ assert (bcp_queue_is_empty (ps));
+ return PICOSAT_UNKNOWN;
+ }
+#endif
+
+ if (ps->fsimplify < ps->fixed && ps->lsimplify <= ps->propagations)
+ {
+ simplify (ps, 0);
+ if (!bcp_queue_is_empty (ps))
+ continue;
+#ifndef NFL
+ if (ps->mtcls)
+ return PICOSAT_UNSATISFIABLE;
+
+ if (satisfied (ps))
+ return PICOSAT_SATISFIABLE;
+
+ assert (!ps->LEVEL);
+#endif
+ }
+
+ if (need_to_reduce (ps))
+ reduce (ps, 50);
--
2.39.2
