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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
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@ -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(); }