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bug fixes

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2017-05-21 15:39:05 -07:00
parent 2d0ab6a615
commit d1fec7c029
3 changed files with 135 additions and 50 deletions
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112
src/ast/rewriter/pb2bv_rewriter.cpp
View file

@ -54,6 +54,8 @@ struct pb2bv_rewriter::imp {
vector<rational> m_coeffs;
bool m_keep_cardinality_constraints;
bool m_keep_pb_constraints;
bool m_pb_num_system;
bool m_pb_totalizer;
unsigned m_min_arity;
template<lbool is_le>
@ -114,23 +116,24 @@ struct pb2bv_rewriter::imp {
return expr_ref((is_le == l_false)?m.mk_true():m.mk_false(), m);
}
#if 0
expr_ref result(m);
switch (is_le) {
case l_true: if (mk_le_tot(sz, args, k, result)) return result; else break;
case l_false: if (mk_ge_tot(sz, args, k, result)) return result; else break;
case l_undef: break;
if (m_pb_totalizer) {
expr_ref result(m);
switch (is_le) {
case l_true: if (mk_le_tot(sz, args, k, result)) return result; else break;
case l_false: if (mk_ge_tot(sz, args, k, result)) return result; else break;
case l_undef: break;
}
}
if (m_pb_num_system) {
expr_ref result(m);
switch (is_le) {
case l_true: if (mk_le(sz, args, k, result)) return result; else break;
case l_false: if (mk_ge(sz, args, k, result)) return result; else break;
case l_undef: if (mk_eq(sz, args, k, result)) return result; else break;
}
}
#endif
#if 0
expr_ref result(m);
switch (is_le) {
case l_true: if (mk_le(sz, args, k, result)) return result; else break;
case l_false: if (mk_ge(sz, args, k, result)) return result; else break;
case l_undef: if (mk_eq(sz, args, k, result)) return result; else break;
}
#endif
// fall back to divide and conquer encoding.
SASSERT(k.is_pos());
expr_ref zero(m), bound(m);
@ -397,22 +400,30 @@ struct pb2bv_rewriter::imp {
for (unsigned j = 0; j + lim - 1 < out.size(); j += n) {
expr_ref tmp(m);
tmp = out[j + lim - 1];
if (j + n < out.size()) {
tmp = m.mk_and(tmp, m.mk_not(out[j + n]));
if (j + n - 1 < out.size()) {
tmp = m.mk_and(tmp, m.mk_not(out[j + n - 1]));
}
ors.push_back(tmp);
}
return ::mk_or(ors);
}
// x0 + 5x1 + 3x2 >= k
// x0 x1 x1 -> s0 s1 s2
// s2 x1 x2 -> s3 s4 s5
// k = 7: s5 or (s4 & not s2 & s0)
// k = 6: s4
// k = 5: s4 or (s3 & not s2 & s1)
// k = 4: s4 or (s3 & not s2 & s0)
// k = 3: s3
//
bool mk_ge(unsigned sz, expr * const* args, rational bound, expr_ref& result) {
if (!create_basis()) return false;
if (!bound.is_unsigned()) return false;
vector<rational> coeffs(m_coeffs);
result = m.mk_true();
expr_ref_vector carry(m), new_carry(m);
for (unsigned i = 0; i < m_base.size(); ++i) {
rational b_i = m_base[i];
for (rational b_i : m_base) {
unsigned B = b_i.get_unsigned();
unsigned d_i = (bound % b_i).get_unsigned();
bound = div(bound, b_i);
@ -425,16 +436,16 @@ struct pb2bv_rewriter::imp {
coeffs[j] = div(coeffs[j], b_i);
}
TRACE("pb", tout << "Carry: " << carry << "\n";
for (unsigned j = 0; j < coeffs.size(); ++j) tout << coeffs[j] << " ";
for (auto c : coeffs) tout << c << " ";
tout << "\n";
);
ptr_vector<expr> out;
m_sort.sorting(carry.size(), carry.c_ptr(), out);
expr_ref gt = mod_ge(out, B, d_i + 1);
expr_ref ge = mod_ge(out, B, d_i);
result = mk_or(gt, mk_and(ge, result));
TRACE("pb", tout << result << "\n";);
TRACE("pb", tout << "b: " << b_i << " d: " << d_i << " gt: " << gt << " ge: " << ge << " " << result << "\n";);
new_carry.reset();
for (unsigned j = B - 1; j < out.size(); j += B) {
@ -443,7 +454,10 @@ struct pb2bv_rewriter::imp {
carry.reset();
carry.append(new_carry);
}
TRACE("pb", tout << result << "\n";);
if (!carry.empty()) {
result = m.mk_or(result, carry[0].get());
}
TRACE("pb", tout << "Carry: " << carry << " result: " << result << "\n";);
return true;
}
@ -567,6 +581,8 @@ struct pb2bv_rewriter::imp {
m_args(m),
m_keep_cardinality_constraints(false),
m_keep_pb_constraints(false),
m_pb_num_system(false),
m_pb_totalizer(false),
m_min_arity(2)
{}
@ -761,6 +777,14 @@ struct pb2bv_rewriter::imp {
void keep_pb_constraints(bool f) {
m_keep_pb_constraints = f;
}
void pb_num_system(bool f) {
m_pb_num_system = f;
}
void pb_totalizer(bool f) {
m_pb_totalizer = f;
}
};
struct card2bv_rewriter_cfg : public default_rewriter_cfg {
@ -774,6 +798,8 @@ struct pb2bv_rewriter::imp {
card2bv_rewriter_cfg(imp& i, ast_manager & m):m_r(i, m) {}
void keep_cardinality_constraints(bool f) { m_r.keep_cardinality_constraints(f); }
void keep_pb_constraints(bool f) { m_r.keep_pb_constraints(f); }
void pb_num_system(bool f) { m_r.pb_num_system(f); }
void pb_totalizer(bool f) { m_r.pb_totalizer(f); }
};
class card_pb_rewriter : public rewriter_tpl<card2bv_rewriter_cfg> {
@ -784,27 +810,59 @@ struct pb2bv_rewriter::imp {
m_cfg(i, m) {}
void keep_cardinality_constraints(bool f) { m_cfg.keep_cardinality_constraints(f); }
void keep_pb_constraints(bool f) { m_cfg.keep_pb_constraints(f); }
void pb_num_system(bool f) { m_cfg.pb_num_system(f); }
void pb_totalizer(bool f) { m_cfg.pb_totalizer(f); }
};
card_pb_rewriter m_rw;
bool keep_cardinality() const {
params_ref const& p = m_params;
return
p.get_bool("keep_cardinality_constraints", false) ||
p.get_bool("sat.cardinality.solver", false) ||
p.get_bool("cardinality.solver", false) || keep_pb();
}
bool keep_pb() const {
params_ref const& p = m_params;
return
p.get_bool("keep_pb_constraints", false) ||
p.get_bool("sat.pb.solver", false) ||
p.get_bool("pb.solver", false);
}
bool pb_num_system() const {
return m_params.get_bool("pb_num_system", false);
}
bool pb_totalizer() const {
return m_params.get_bool("pb_totalizer", false);
}
imp(ast_manager& m, params_ref const& p):
m(m), m_params(p), m_lemmas(m),
m_fresh(m),
m_num_translated(0),
m_rw(*this, m) {
m_rw.keep_cardinality_constraints(p.get_bool("keep_cardinality_constraints", false));
m_rw.keep_pb_constraints(p.get_bool("keep_pb_constraints", false));
m_rw.keep_cardinality_constraints(keep_cardinality());
m_rw.keep_pb_constraints(keep_pb());
m_rw.pb_num_system(pb_num_system());
m_rw.pb_totalizer(pb_totalizer());
}
void updt_params(params_ref const & p) {
m_params.append(p);
m_rw.keep_cardinality_constraints(m_params.get_bool("keep_cardinality_constraints", false));
m_rw.keep_pb_constraints(m_params.get_bool("keep_pb_constraints", false));
m_rw.keep_cardinality_constraints(keep_cardinality());
m_rw.keep_pb_constraints(keep_pb());
m_rw.pb_num_system(pb_num_system());
m_rw.pb_totalizer(pb_totalizer());
}
void collect_param_descrs(param_descrs& r) const {
r.insert("keep_cardinality_constraints", CPK_BOOL, "(default: true) retain cardinality constraints (don't bit-blast them) and use built-in cardinality solver");
r.insert("keep_pb_constraints", CPK_BOOL, "(default: true) retain pb constraints (don't bit-blast them) and use built-in pb solver");
r.insert("pb_num_system", CPK_BOOL, "(default: false) use pb number system encoding");
r.insert("pb_totalizer", CPK_BOOL, "(default: false) use pb totalizer encoding");
}
unsigned get_num_steps() const { return m_rw.get_num_steps(); }

65
src/sat/card_extension.cpp
View file

@ -250,7 +250,7 @@ namespace sat {
p.swap(i, j);
}
if (slack < bound) {
slack += p[i].first;
slack += p[j].first;
++num_watch;
}
++j;
@ -267,7 +267,7 @@ namespace sat {
if (slack < bound) {
literal lit = p[j].second;
SASSERT(value(p[j].second) == l_false);
for (unsigned i = j + 1; j < sz; ++i) {
for (unsigned i = j + 1; i < sz; ++i) {
if (lvl(lit) < lvl(p[i].second)) {
lit = p[i].second;
}
@ -386,16 +386,24 @@ namespace sat {
p.swap(num_watch, index);
if (slack < bound + m_a_max) {
while (!s().inconsistent() && !m_pb_undef.empty()) {
TRACE("sat", display(tout, p, false); for(auto j : m_pb_undef) tout << j << "\n";);
literal_vector to_assign;
while (!m_pb_undef.empty()) {
index1 = m_pb_undef.back();
literal lit = p[index1].second;
TRACE("sat", tout << index1 << " " << lit << "\n";);
if (slack >= bound + p[index1].first) {
break;
}
m_pb_undef.pop_back();
to_assign.push_back(lit);
}
for (literal lit : to_assign) {
if (s().inconsistent()) break;
if (value(lit) == l_undef) {
assign(p, lit);
}
}
}
}
@ -474,7 +482,8 @@ namespace sat {
}
void card_extension::display(std::ostream& out, pb const& p, bool values) const {
out << p.lit() << "[ watch: " << p.num_watch() << ", slack: " << p.slack() << "]";
if (p.lit() != null_literal) out << p.lit();
out << "[watch: " << p.num_watch() << ", slack: " << p.slack() << "]";
if (p.lit() != null_literal && values) {
out << "@(" << value(p.lit());
if (value(p.lit()) != l_undef) {
@ -1350,7 +1359,25 @@ namespace sat {
if (p.lit() != null_literal) r.push_back(p.lit());
SASSERT(p.lit() == null_literal || value(p.lit()) == l_true);
TRACE("sat", display(tout, p, true););
for (unsigned i = p.num_watch(); i < p.size(); ++i) {
// unsigned coeff = get_coeff(p, l);
unsigned coeff = 0;
for (unsigned j = 0; j < p.num_watch(); ++j) {
if (p[j].second == l) {
coeff = p[j].first;
break;
}
}
unsigned slack = p.slack() - coeff;
unsigned i = p.num_watch();
// skip entries that are not required for unit propagation.
// slack - coeff + w_head < k
unsigned h = 0;
for (; i < p.size() && p[i].first + h + slack < p.k(); ++i) {
h += p[i].first;
}
for (; i < p.size(); ++i) {
literal lit = p[i].second;
SASSERT(l_false == value(lit));
r.push_back(~lit);
@ -1714,7 +1741,9 @@ namespace sat {
std::ostream& card_extension::display_justification(std::ostream& out, ext_justification_idx idx) const {
if (is_card_index(idx)) {
card& c = index2card(idx);
out << "bound " << c.lit() << ": ";
out << "bound ";
if (c.lit() != null_literal) out << c.lit();
out << ": ";
for (unsigned i = 0; i < c.size(); ++i) {
out << c[i] << " ";
}
@ -1722,14 +1751,18 @@ namespace sat {
}
else if (is_xor_index(idx)) {
xor& x = index2xor(idx);
out << "xor " << x.lit() << ": ";
out << "xor ";
if (x.lit() != null_literal) out << x.lit();
out << ": ";
for (unsigned i = 0; i < x.size(); ++i) {
out << x[i] << " ";
}
}
else if (is_pb_index(idx)) {
pb& p = index2pb(idx);
out << "pb " << p.lit() << ": ";
out << "pb ";
if (p.lit() != null_literal) out << p.lit();
out << ": ";
for (unsigned i = 0; i < p.size(); ++i) {
out << p[i].first << "*" << p[i].second << " ";
}
@ -1773,26 +1806,16 @@ namespace sat {
bool card_extension::validate_unit_propagation(pb const& p, literal alit) {
if (p.lit() != null_literal && value(p.lit()) != l_true) return false;
unsigned k = p.k();
unsigned sum = 0;
unsigned a_min = 0;
TRACE("sat", display(tout << "validate: " << alit << "\n", p, true););
for (unsigned i = 0; i < p.size(); ++i) {
literal lit = p[i].second;
lbool val = value(lit);
if (val == l_false) {
// no-op
}
else if (lit == alit) {
a_min = p[i].first;
sum += p[i].first;
}
else {
if (val != l_false && lit != alit) {
sum += p[i].first;
}
}
return sum < k + a_min;
return true;
return sum < p.k();
}
bool card_extension::validate_lemma() {

8
src/tactic/portfolio/pb2bv_solver.cpp
View file

@ -20,6 +20,7 @@ Notes:
#include "solver_na2as.h"
#include "tactic.h"
#include "pb2bv_rewriter.h"
#include "th_rewriter.h"
#include "filter_model_converter.h"
#include "ast_pp.h"
#include "model_smt2_pp.h"
@ -29,6 +30,7 @@ class pb2bv_solver : public solver_na2as {
params_ref m_params;
mutable expr_ref_vector m_assertions;
mutable ref<solver> m_solver;
mutable th_rewriter m_th_rewriter;
mutable pb2bv_rewriter m_rewriter;
public:
@ -39,6 +41,7 @@ public:
m_params(p),
m_assertions(m),
m_solver(s),
m_th_rewriter(m, p),
m_rewriter(m, p)
{
}
@ -121,10 +124,11 @@ public:
private:
void flush_assertions() const {
proof_ref proof(m);
expr_ref fml(m);
expr_ref fml1(m), fml(m);
expr_ref_vector fmls(m);
for (unsigned i = 0; i < m_assertions.size(); ++i) {
m_rewriter(m_assertions[i].get(), fml, proof);
m_th_rewriter(m_assertions[i].get(), fml1, proof);
m_rewriter(fml1, fml, proof);
m_solver->assert_expr(fml);
}
m_rewriter.flush_side_constraints(fmls);