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adding drat

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2017-02-03 15:41:08 -08:00
parent 505133a4b3
commit 0b711c5ef8
14 changed files with 255 additions and 53 deletions
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126
src/sat/card_extension.cpp
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@ -94,7 +94,7 @@ namespace sat {
alit = c[j];
}
}
set_conflict(c, alit);
set_conflict(c);
}
else if (j == bound) {
for (unsigned i = 0; i < bound && !s().inconsistent(); ++i) {
@ -136,32 +136,40 @@ namespace sat {
}
void card_extension::assign(card& c, literal lit) {
if (value(lit) == l_true) {
return;
switch (value(lit)) {
case l_true:
break;
case l_false:
set_conflict(c);
break;
default:
m_stats.m_num_propagations++;
//TRACE("sat", tout << "#prop: " << m_stats.m_num_propagations << " - " << c.lit() << " => " << lit << "\n";);
SASSERT(validate_unit_propagation(c));
s().assign(lit, justification::mk_ext_justification(c.index()));
break;
}
m_stats.m_num_propagations++;
//TRACE("sat", tout << "#prop: " << m_stats.m_num_propagations << " - " << c.lit() << " => " << lit << "\n";);
SASSERT(validate_unit_propagation(c));
s().assign(lit, justification::mk_ext_justification(c.index()));
}
void card_extension::watch_literal(card& c, literal lit) {
TRACE("sat", tout << "watch: " << lit << "\n";);
TRACE("sat_verbose", tout << "watch: " << lit << "\n";);
init_watch(lit.var());
ptr_vector<card>* cards = m_var_infos[lit.var()].m_lit_watch[lit.sign()];
if (cards == 0) {
cards = alloc(ptr_vector<card>);
m_var_infos[lit.var()].m_lit_watch[lit.sign()] = cards;
}
TRACE("sat", tout << "insert: " << lit.var() << " " << lit.sign() << "\n";);
TRACE("sat_verbose", tout << "insert: " << lit.var() << " " << lit.sign() << "\n";);
cards->push_back(&c);
}
void card_extension::set_conflict(card& c, literal lit) {
void card_extension::set_conflict(card& c) {
TRACE("sat", display(tout, c, true); );
SASSERT(validate_conflict(c));
m_stats.m_num_conflicts++;
if (!resolve_conflict(c, lit)) {
literal lit = last_false_literal(c);
if (!resolve_conflict(c, lit)) {
TRACE("sat", tout << "bail out conflict resolution\n";);
m_conflict.reset();
m_conflict.push_back(~c.lit());
unsigned sz = c.size();
@ -169,11 +177,40 @@ namespace sat {
m_conflict.push_back(c[i]);
}
m_conflict.push_back(lit);
SASSERT(validate_conflict(m_conflict));
// SASSERT(validate_conflict(m_conflict));
s().assign(lit, justification::mk_ext_justification(0));
}
SASSERT(s().inconsistent());
}
literal card_extension::last_false_literal(card& c) {
while (!m_active_var_set.empty()) m_active_var_set.erase();
reset_coeffs();
for (unsigned i = 0; i < c.size(); ++i) {
bool_var v = c[i].var();
m_active_var_set.insert(v);
m_active_vars.push_back(v);
m_coeffs.setx(v, c[i].sign() ? -1 : 1, 0);
}
literal_vector const& lits = s().m_trail;
for (unsigned i = lits.size(); i > 0; ) {
--i;
literal lit = lits[i];
bool_var v = lit.var();
if (m_active_var_set.contains(v) &&
(m_coeffs[v] > 0 == lits[i].sign())) {
//std::cout << "last literal: " << lit << "\n";
for (unsigned j = 0; j < c.size(); ++j) {
if (~lit == c[j] && j != c.k()-1) {
// std::cout << "POSITION " << j << " bound " << c.k() << "\n";
}
}
return ~lit;
}
}
UNREACHABLE();
return null_literal;
}
void card_extension::normalize_active_coeffs() {
while (!m_active_var_set.empty()) m_active_var_set.erase();
@ -244,7 +281,7 @@ namespace sat {
if (m_conflict_lvl < lvl(c.lit()) || m_conflict_lvl == 0) {
return false;
}
std::cout << "conflict level: " << m_conflict_lvl << " " << lvl(~alit) << "\n";
// std::cout << "conflict level: " << m_conflict_lvl << " " << lvl(~alit) << "\n";
reset_coeffs();
m_num_marks = 0;
@ -263,6 +300,8 @@ namespace sat {
v = consequent.var();
int offset = get_abs_coeff(v);
// TRACE("sat", display(tout, m_A););
if (offset == 0) {
goto process_next_resolvent;
}
@ -365,12 +404,14 @@ namespace sat {
bool_var v = m_active_vars[i];
slack += get_abs_coeff(v);
}
TRACE("sat", display(tout, m_A););
++idx;
alit = null_literal;
#if 1
std::cout << c.size() << " >= " << c.k() << "\n";
std::cout << m_active_vars.size() << ": " << slack + m_bound << " >= " << m_bound << "\n";
// std::cout << c.size() << " >= " << c.k() << "\n";
// std::cout << m_active_vars.size() << ": " << slack + m_bound << " >= " << m_bound << "\n";
while (0 <= slack) {
literal lit = lits[idx];
bool_var v = lit.var();
@ -432,7 +473,9 @@ namespace sat {
return false;
}
SASSERT(slack < 0);
SASSERT(validate_conflict(m_conflict));
SASSERT(validate_conflict(m_conflict, m_A));
TRACE("sat", tout << m_conflict << "\n";);
s().assign(alit, justification::mk_ext_justification(0));
return true;
@ -520,7 +563,7 @@ namespace sat {
void card_extension::get_antecedents(literal l, ext_justification_idx idx, literal_vector & r) {
if (idx == 0) {
std::cout << "antecedents0: " << l << " " << m_conflict.size() << "\n";
// std::cout << "antecedents0: " << l << " " << m_conflict.size() << "\n";
SASSERT(m_conflict.back() == l);
for (unsigned i = 0; i + 1 < m_conflict.size(); ++i) {
SASSERT(value(m_conflict[i]) == l_false);
@ -537,7 +580,7 @@ namespace sat {
}
SASSERT(found););
std::cout << "antecedents: " << idx << ": " << l << " " << c.size() - c.k() + 1 << "\n";
// std::cout << "antecedents: " << idx << ": " << l << " " << c.size() - c.k() + 1 << "\n";
r.push_back(c.lit());
SASSERT(value(c.lit()) == l_true);
for (unsigned i = c.k(); i < c.size(); ++i) {
@ -552,7 +595,7 @@ namespace sat {
// literal is assigned to false.
unsigned sz = c.size();
unsigned bound = c.k();
TRACE("sat", tout << "assign: " << c.lit() << " " << ~alit << " " << bound << "\n";);
TRACE("sat", tout << "assign: " << c.lit() << ": " << ~alit << "@" << lvl(~alit) << "\n";);
SASSERT(0 < bound && bound < sz);
SASSERT(value(alit) == l_false);
@ -583,11 +626,11 @@ namespace sat {
// conflict
if (bound != index && value(c[bound]) == l_false) {
TRACE("sat", tout << "conflict " << c[bound] << " " << alit << "\n";);
set_conflict(c, alit);
set_conflict(c);
return l_false;
}
TRACE("sat", tout << "no swap " << index << " " << alit << "\n";);
// TRACE("sat", tout << "no swap " << index << " " << alit << "\n";);
// there are no literals to swap with,
// prepare for unit propagation by swapping the false literal into
// position bound. Then literals in positions 0..bound-1 have to be
@ -609,8 +652,8 @@ namespace sat {
if (v >= m_var_infos.size()) return;
var_info& vinfo = m_var_infos[v];
ptr_vector<card>* cards = vinfo.m_lit_watch[!l.sign()];
TRACE("sat", tout << "retrieve: " << v << " " << !l.sign() << "\n";);
TRACE("sat", tout << "asserted: " << l << " " << (cards ? "non-empty" : "empty") << "\n";);
//TRACE("sat", tout << "retrieve: " << v << " " << !l.sign() << "\n";);
//TRACE("sat", tout << "asserted: " << l << " " << (cards ? "non-empty" : "empty") << "\n";);
if (cards != 0 && !cards->empty() && !s().inconsistent()) {
ptr_vector<card>::iterator it = cards->begin(), it2 = it, end = cards->end();
for (; it != end; ++it) {
@ -652,7 +695,7 @@ namespace sat {
}
void card_extension::pop(unsigned n) {
TRACE("sat", tout << "pop:" << n << "\n";);
TRACE("sat_verbose", tout << "pop:" << n << "\n";);
unsigned new_lim = m_var_lim.size() - n;
unsigned sz = m_var_lim[new_lim];
while (m_var_trail.size() > sz) {
@ -690,9 +733,9 @@ namespace sat {
void card_extension::display_watch(std::ostream& out, bool_var v, bool sign) const {
watch const* w = m_var_infos[v].m_lit_watch[sign];
if (w) {
if (w && !w->empty()) {
watch const& wl = *w;
out << "watch: " << literal(v, sign) << " |-> ";
out << literal(v, sign) << " |-> ";
for (unsigned i = 0; i < wl.size(); ++i) {
out << wl[i]->lit() << " ";
}
@ -708,7 +751,7 @@ namespace sat {
}
void card_extension::display(std::ostream& out, card& c, bool values) const {
out << c.lit();
out << c.lit() << "[" << c.size() << "]";
if (c.lit() != null_literal && values) {
out << "@(" << value(c.lit());
if (value(c.lit()) != l_undef) {
@ -750,6 +793,21 @@ namespace sat {
return out;
}
std::ostream& card_extension::display_justification(std::ostream& out, ext_justification_idx idx) const {
if (idx == 0) {
out << "conflict: " << m_conflict;
}
else {
card& c = *m_constraints[idx];
out << "bound " << c.lit() << ": ";
for (unsigned i = c.k(); i < c.size(); ++i) {
out << c[i] << " ";
}
out << ">= " << c.k();
}
return out;
}
void card_extension::collect_statistics(statistics& st) const {
st.update("cardinality propagations", m_stats.m_num_propagations);
st.update("cardinality conflicts", m_stats.m_num_conflicts);
@ -842,7 +900,6 @@ namespace sat {
// validate that m_A & m_B implies m_C
bool card_extension::validate_resolvent() {
std::cout << "validate resolvent\n";
u_map<unsigned> coeffs;
unsigned k = m_A.m_k + m_B.m_k;
for (unsigned i = 0; i < m_A.m_lits.size(); ++i) {
@ -899,11 +956,18 @@ namespace sat {
return true;
}
bool card_extension::validate_conflict(literal_vector const& lits) {
bool card_extension::validate_conflict(literal_vector const& lits, ineq& p) {
for (unsigned i = 0; i < lits.size(); ++i) {
if (value(lits[i]) != l_false) return false;
}
return true;
unsigned value = 0;
for (unsigned i = 0; i < p.m_lits.size(); ++i) {
unsigned coeff = p.m_coeffs[i];
if (!lits.contains(p.m_lits[i])) {
value += coeff;
}
}
return value < p.m_k;
}