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maxres revised to handle weighted constraints

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-07-22 15:42:08 +02:00
parent bf35a62da7
commit 5e9bf2ef53
5 changed files with 177 additions and 83 deletions
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60
src/opt/mus.cpp
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@ -16,9 +16,21 @@ struct mus::imp {
vector<smt::literal_vector> m_cls2lits;
expr_ref_vector m_vars;
obj_map<expr, unsigned> m_var2idx;
volatile bool m_cancel;
public:
imp(solver& s, ast_manager& m): s(s), m(m), m_cls2expr(m), m_vars(m) {}
imp(solver& s, ast_manager& m): s(s), m(m), m_cls2expr(m), m_vars(m), m_cancel(false) {}
void reset() {
m_cls2expr.reset();
m_expr2cls.reset();
m_cls2lits.reset();
m_vars.reset();
m_var2idx.reset();
}
void set_cancel(bool f) {
m_cancel = f;
}
unsigned add_var(expr* v) {
unsigned idx = m_vars.size();
@ -47,10 +59,16 @@ public:
m_cls2lits.push_back(lits);
return idx;
}
expr* mk_not(expr* e) {
if (m.is_not(e, e)) {
return e;
}
return m.mk_not(e);
}
lbool get_mus(unsigned_vector& mus) {
TRACE("opt", tout << "\n";);
solver::scoped_push _sc(s);
unsigned_vector core;
for (unsigned i = 0; i < m_cls2expr.size(); ++i) {
core.push_back(i);
@ -61,12 +79,17 @@ public:
ptr_vector<expr> core_exprs;
model.resize(m_vars.size());
while (!core.empty()) {
IF_VERBOSE(0, display_vec(tout << "core: ", core););
TRACE("opt",
display_vec(tout << "core: ", core);
display_vec(tout << "mus: ", mus);
display_vec(tout << "model: ", model);
);
IF_VERBOSE(1, verbose_stream() << "(opt.mus reducing core: " << core.size() << " new core: " << mus.size() << ")\n";);
unsigned cls_id = core.back();
core.pop_back();
expr* cls = m_cls2expr[cls_id].get();
expr_ref not_cls(m);
not_cls = m.mk_not(cls);
not_cls = mk_not(cls);
unsigned sz = assumptions.size();
assumptions.push_back(not_cls);
add_core(core, assumptions);
@ -113,7 +136,7 @@ public:
template<class T>
void display_vec(std::ostream& out, T const& v) const {
for (unsigned i = 0; i < v.size(); ++i) {
out << mk_pp(v[i], m) << " ";
out << v[i] << " ";
}
out << "\n";
}
@ -133,19 +156,18 @@ public:
*/
void rmr(unsigned_vector& M, unsigned_vector& mus, svector<bool>& model) {
TRACE("opt",
display_vec(tout << "M:", M);
display_vec(tout << "mus:", mus);
display_vec(tout << "model:", model););
display_vec(tout << "core: ", M);
display_vec(tout << "mus: ", mus);
display_vec(tout << "model: ", model););
unsigned cls_id = mus.back();
smt::literal_vector const& cls = m_cls2lits[cls_id];
unsigned cls_id_new;
for (unsigned i = 0; i < cls.size(); ++i) {
smt::literal lit = cls[i];
SASSERT(model[lit.var()] == lit.sign()); // literal evaluates to false.
model[lit.var()] = !model[lit.var()]; // swap assignment
if (has_single_unsat(model, cls_id_new)) {
mus.push_back(cls_id_new);
if (!mus.contains(cls_id) && has_single_unsat(model, cls_id)) {
mus.push_back(cls_id);
rmr(M, mus, model);
}
model[lit.var()] = !model[lit.var()]; // swap assignment back
@ -176,13 +198,6 @@ public:
return false;
}
template<class T>
void display_vec(std::ostream& out, T const& v) {
for (unsigned i = 0; i < v.size(); ++i) {
out << v[i] << " ";
}
out << "\n";
}
};
mus::mus(solver& s, ast_manager& m) {
@ -201,3 +216,10 @@ lbool mus::get_mus(unsigned_vector& mus) {
return m_imp->get_mus(mus);
}
void mus::set_cancel(bool f) {
m_imp->set_cancel(f);
}
void mus::reset() {
m_imp->reset();
}