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integrate v2 of lns

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This commit is contained in:
Nikolaj Bjorner 2021-02-04 15:47:40 -08:00
parent dfb7c87448
commit 0ec567fe15
18 changed files with 254 additions and 105 deletions
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55
src/opt/maxres.cpp
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@ -83,6 +83,18 @@ private:
memset(this, 0, sizeof(*this));
}
};
struct lns_maxres : public lns_context {
maxres& i;
lns_maxres(maxres& i) :i(i) {}
~lns_maxres() override {}
void update_model(model_ref& mdl) override { i.update_assignment(mdl); }
void relax_cores(vector<expr_ref_vector> const& cores) override { i.relax_cores(cores); }
rational cost(model& mdl) override { return i.cost(mdl); }
rational weight(expr* e) override { return i.m_asm2weight[e]; }
expr_ref_vector const& soft() override { return i.m_asms; }
};
unsigned m_index;
stats m_stats;
expr_ref_vector m_B;
@ -95,6 +107,8 @@ private:
strategy_t m_st;
rational m_max_upper;
model_ref m_csmodel;
lns_maxres m_lnsctx;
lns m_lns;
unsigned m_correction_set_size;
bool m_found_feasible_optimum;
bool m_hill_climb; // prefer large weight soft clauses for cores
@ -125,6 +139,8 @@ public:
m_mus(c.get_solver()),
m_trail(m),
m_st(st),
m_lnsctx(*this),
m_lns(s(), m_lnsctx),
m_correction_set_size(0),
m_found_feasible_optimum(false),
m_hill_climb(true),
@ -507,9 +523,10 @@ public:
void update_model(expr* def, expr* value) {
SASSERT(is_uninterp_const(def));
if (m_csmodel) {
m_csmodel->register_decl(to_app(def)->get_decl(), (*m_csmodel)(value));
}
if (m_csmodel)
m_csmodel->register_decl(to_app(def)->get_decl(), (*m_csmodel)(value));
if (m_model)
m_model->register_decl(to_app(def)->get_decl(), (*m_model)(value));
}
void process_unsat(exprs const& core, rational w) {
@ -729,7 +746,7 @@ public:
fml = m.mk_and(b_i1, cls);
update_model(asum, fml);
}
fml = m.mk_or(cs.size(), cs.c_ptr());
fml = m.mk_or(cs);
add(fml);
}
@ -742,21 +759,13 @@ public:
update_assignment(mdl);
}
void improve_model(model_ref& mdl) {
if (!m_enable_lns)
return;
flet<bool> _disable_lns(m_enable_lns, false);
std::function<void(model_ref&)> update_model = [&](model_ref& mdl) {
update_assignment(mdl);
};
std::function<void(vector<expr_ref_vector> const&)> _relax_cores = [&](vector<expr_ref_vector> const& cores) {
relax_cores(cores);
};
lns lns(s(), update_model);
lns.set_conflicts(m_lns_conflicts);
lns.set_relax(_relax_cores);
lns.climb(mdl, m_asms);
m_lns.climb(mdl);
}
void relax_cores(vector<expr_ref_vector> const& cores) {
@ -770,6 +779,13 @@ public:
process_unsat(wcores);
}
rational cost(model& mdl) {
rational upper(0);
for (soft& s : m_soft)
if (!mdl.is_true(s.s))
upper += s.weight;
return upper;
}
void update_assignment(model_ref & mdl) {
improve_model(mdl);
@ -787,14 +803,7 @@ public:
TRACE("opt_verbose", tout << *mdl;);
rational upper(0);
for (soft& s : m_soft) {
TRACE("opt", tout << s.s << ": " << (*mdl)(s.s) << " " << s.weight << "\n";);
if (!mdl->is_true(s.s)) {
upper += s.weight;
}
}
rational upper = cost(*mdl);
if (upper > m_upper) {
TRACE("opt", tout << "new upper: " << upper << " vs existing upper: " << m_upper << "\n";);