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integrating diff opt

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-03-05 16:29:26 -08:00
parent 80ba830091
commit 99b4ce037d
10 changed files with 67 additions and 59 deletions

View file

@ -312,18 +312,17 @@ namespace opt {
mk_simplify_tactic(m));
tactic_ref tac2 = mk_elim01_tactic(m);
tactic_ref tac3 = mk_lia2card_tactic(m);
tactic_ref tac;
opt_params optp(m_params);
if (optp.elim_01()) {
tac = and_then(tac0.get(), tac2.get(), tac3.get());
m_simplify = and_then(tac0.get(), tac2.get(), tac3.get());
}
else {
tac = tac0.get();
m_simplify = tac0.get();
}
proof_converter_ref pc;
expr_dependency_ref core(m);
goal_ref_buffer result;
(*tac)(g, result, m_model_converter, pc, core); // TBD: have this an attribute so we can cancel.
(*m_simplify)(g, result, m_model_converter, pc, core);
SASSERT(result.size() == 1);
goal* r = result[0];
fmls.reset();
@ -708,6 +707,9 @@ namespace opt {
if (m_solver) {
m_solver->set_cancel(f);
}
if (m_simplify) {
m_simplify->set_cancel(f);
}
m_optsmt.set_cancel(f);
map_t::iterator it = m_maxsmts.begin(), end = m_maxsmts.end();
for (; it != end; ++it) {
@ -719,6 +721,9 @@ namespace opt {
if (m_solver) {
m_solver->collect_statistics(stats);
}
if (m_simplify) {
m_simplify->collect_statistics(stats);
}
map_t::iterator it = m_maxsmts.begin(), end = m_maxsmts.end();
for (; it != end; ++it) {
it->m_value->collect_statistics(stats);

View file

@ -30,6 +30,7 @@ Notes:
#include "optsmt.h"
#include "maxsmt.h"
#include "model_converter.h"
#include "tactic.h"
namespace opt {
@ -89,6 +90,7 @@ namespace opt {
obj_map<func_decl, unsigned> m_objective_fns;
obj_map<func_decl, expr*> m_objective_orig;
func_decl_ref_vector m_objective_refs;
tactic_ref m_simplify;
public:
context(ast_manager& m);
~context();

View file

@ -133,15 +133,17 @@ namespace opt {
return r;
}
void opt_solver::maximize_objectives() {
void opt_solver::maximize_objectives(expr_ref_vector& blockers) {
expr_ref blocker(m);
for (unsigned i = 0; i < m_objective_vars.size(); ++i) {
maximize_objective(i);
maximize_objective(i, blocker);
blockers.push_back(blocker);
}
}
void opt_solver::maximize_objective(unsigned i) {
void opt_solver::maximize_objective(unsigned i, expr_ref& blocker) {
smt::theory_var v = m_objective_vars[i];
m_objective_values[i] = get_optimizer().maximize(v);
m_objective_values[i] = get_optimizer().maximize(v, blocker);
m_context.get_context().update_model();
TRACE("opt", { model_ref mdl; get_model(mdl); model_smt2_pp(tout << "update model: ", m, *mdl, 0); });
}
@ -231,20 +233,7 @@ namespace opt {
// difference logic?
return expr_ref(m.mk_true(), m);
}
expr_ref opt_solver::mk_gt(unsigned var, inf_eps const& val) {
if (val.get_infinity().is_pos()) {
return expr_ref(m.mk_false(), m);
}
else if (val.get_infinity().is_neg()) {
return expr_ref(m.mk_true(), m);
}
else {
inf_rational n = val.get_numeral();
return expr_ref(get_optimizer().mk_gt(m_objective_vars[var], n), m);
}
}
}
void opt_solver::reset_objectives() {
m_objective_vars.reset();

View file

@ -75,12 +75,11 @@ namespace opt {
smt::theory_var add_objective(app* term);
void reset_objectives();
void maximize_objective(unsigned i);
void maximize_objectives();
void maximize_objective(unsigned i, expr_ref& blocker);
void maximize_objectives(expr_ref_vector& blockers);
vector<inf_eps> const& get_objective_values();
inf_eps const & get_objective_value(unsigned obj_index);
expr_ref mk_gt(unsigned obj_index, inf_eps const& val);
expr_ref mk_ge(unsigned obj_index, inf_eps const& val);
filter_model_converter& mc() { return m_fm; }

View file

@ -124,7 +124,8 @@ namespace opt {
}
void optsmt::update_lower() {
m_s->maximize_objectives();
expr_ref_vector disj(m);
m_s->maximize_objectives(disj);
m_s->get_model(m_model);
set_max(m_lower, m_s->get_objective_values());
IF_VERBOSE(1,
@ -134,13 +135,7 @@ namespace opt {
verbose_stream() << "\n";
model_pp(verbose_stream(), *m_model);
);
expr_ref_vector disj(m);
expr_ref constraint(m);
for (unsigned i = 0; i < m_lower.size(); ++i) {
inf_eps const& v = m_lower[i];
disj.push_back(m_s->mk_gt(i, v));
}
expr_ref constraint(m);
constraint = m.mk_or(disj.size(), disj.c_ptr());
m_s->assert_expr(constraint);
}
@ -237,25 +232,23 @@ namespace opt {
lbool optsmt::basic_lex(unsigned obj_index) {
lbool is_sat = l_true;
expr_ref block(m);
expr_ref block(m), tmp(m);
while (is_sat == l_true && !m_cancel) {
is_sat = m_s->check_sat(0, 0);
if (is_sat != l_true) break;
m_s->maximize_objective(obj_index);
m_s->maximize_objective(obj_index, block);
m_s->get_model(m_model);
inf_eps obj = m_s->get_objective_value(obj_index);
if (obj > m_lower[obj_index]) {
m_lower[obj_index] = obj;
IF_VERBOSE(1, verbose_stream() << "(optsmt lower bound: " << obj << ")\n";);
for (unsigned i = obj_index+1; i < m_vars.size(); ++i) {
m_s->maximize_objective(i);
m_s->maximize_objective(i, tmp);
m_lower[i] = m_s->get_objective_value(i);
}
}
block = m_s->mk_gt(obj_index, obj);
m_s->assert_expr(block);
// TBD: only works for simplex
@ -289,14 +282,13 @@ namespace opt {
is_sat = m_s->check_sat(0, 0);
if (is_sat != l_true) break;
was_sat = true;
m_s->maximize_objective(obj_index);
m_s->maximize_objective(obj_index, block);
m_s->get_model(m_model);
inf_eps obj = m_s->get_objective_value(obj_index);
if (obj > m_lower[obj_index]) {
m_lower[obj_index] = obj;
IF_VERBOSE(1, verbose_stream() << "(optsmt lower bound: " << obj << ")\n";);
}
block = m_s->mk_gt(obj_index, obj);
m_s->assert_expr(block);
}
@ -347,10 +339,12 @@ namespace opt {
inf_eps optsmt::get_lower(unsigned i) const {
if (i >= m_lower.size()) return inf_eps();
return m_lower[i];
}
inf_eps optsmt::get_upper(unsigned i) const {
if (i >= m_upper.size()) return inf_eps();
return m_upper[i];
}

View file

@ -998,9 +998,8 @@ namespace smt {
// Optimization
//
// -----------------------------------
virtual inf_eps_rational<inf_rational> maximize(theory_var v);
virtual inf_eps_rational<inf_rational> maximize(theory_var v, expr_ref& blocker);
virtual theory_var add_objective(app* term);
virtual expr* mk_gt(theory_var v, inf_rational const& val);
virtual expr* mk_ge(filter_model_converter& fm, theory_var v, inf_numeral const& val);
void enable_record_conflict(expr* bound);
void record_conflict(unsigned num_lits, literal const * lits,
@ -1008,6 +1007,8 @@ namespace smt {
unsigned num_params, parameter* params);
inf_eps_rational<inf_rational> conflict_minimize();
private:
virtual expr_ref mk_gt(theory_var v);
bool_var m_bound_watch;
inf_eps_rational<inf_rational> m_upper_bound;
bool get_theory_vars(expr * n, uint_set & vars);

View file

@ -1065,13 +1065,17 @@ namespace smt {
}
template<typename Ext>
inf_eps_rational<inf_rational> theory_arith<Ext>::maximize(theory_var v) {
inf_eps_rational<inf_rational> theory_arith<Ext>::maximize(theory_var v, expr_ref& blocker) {
TRACE("opt", tout << "data-size: " << m_data.size() << "\n";);
max_min_t r = max_min(v, true);
if (r == UNBOUNDED) {
blocker = get_manager().mk_false();
return inf_eps_rational<inf_rational>::infinity();
}
return inf_eps_rational<inf_rational>(get_value(v));
else {
blocker = mk_gt(v);
return inf_eps_rational<inf_rational>(get_value(v));
}
}
@ -1081,8 +1085,9 @@ namespace smt {
for the theory of aritmetic.
*/
template<typename Ext>
expr* theory_arith<Ext>::mk_gt(theory_var v, inf_rational const& val) {
expr_ref theory_arith<Ext>::mk_gt(theory_var v) {
ast_manager& m = get_manager();
inf_numeral const& val = get_value(v);
expr* obj = get_enode(v)->get_owner();
expr_ref e(m);
rational r = val.get_rational();
@ -1094,19 +1099,20 @@ namespace smt {
r = ceil(r);
}
e = m_util.mk_numeral(r, m.get_sort(obj));
return m_util.mk_ge(obj, e);
e = m_util.mk_ge(obj, e);
}
else {
// obj is over the reals.
e = m_util.mk_numeral(r, m.get_sort(obj));
if (val.get_infinitesimal().is_neg()) {
return m_util.mk_ge(obj, e);
e = m_util.mk_ge(obj, e);
}
else {
return m_util.mk_gt(obj, e);
e = m_util.mk_gt(obj, e);
}
}
return e;
}
/**

View file

@ -308,9 +308,9 @@ namespace smt {
//
// -----------------------------------
virtual inf_eps_rational<inf_rational> maximize(theory_var v);
virtual inf_eps_rational<inf_rational> maximize(theory_var v, expr_ref& blocker);
virtual theory_var add_objective(app* term);
virtual expr* mk_gt(theory_var v, inf_rational const& val);
virtual expr_ref mk_gt(theory_var v, inf_rational const& val);
virtual expr* mk_ge(theory_var v, inf_rational const& val) { return 0; }
bool internalize_objective(expr * n, rational const& m, rational& r, objective_term & objective);

View file

@ -999,10 +999,11 @@ void theory_diff_logic<Ext>::get_implied_bound_antecedents(edge_id bridge_edge,
}
template<typename Ext>
inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v) {
inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v, expr_ref& blocker) {
typedef simplex::simplex<simplex::mpq_ext> Simplex;
Simplex S;
ast_manager& m = get_manager();
objective_term const& objective = m_objectives[v];
IF_VERBOSE(1,
@ -1067,30 +1068,37 @@ inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v) {
// optimize
lbool is_sat = S.make_feasible();
if (is_sat == l_undef) {
blocker = m.mk_false();
return inf_eps_rational<inf_rational>::infinity();
}
TRACE("opt", S.display(tout); );
TRACE("opt", S.display(tout); );
SASSERT(is_sat != l_false);
lbool is_fin = S.minimize(w);
switch (is_fin) {
case l_true: {
simplex::mpq_ext::eps_numeral const& val = S.get_value(w);
inf_rational r(-rational(val.first), -rational(val.second));
TRACE("opt", tout << r << " " << "\n"; );
TRACE("opt", tout << r << " " << "\n";
S.display_row(tout, row, true););
Simplex::row_iterator it = S.row_begin(row), end = S.row_end(row);
S.display_row(std::cout, row, true);
expr_ref_vector& core = m_objective_assignments[v];
expr_ref tmp(m);
core.reset();
for (; it != end; ++it) {
unsigned v = it->m_var;
if (num_nodes <= v && v < num_nodes + num_edges) {
unsigned edge_id = v - num_nodes;
literal lit = m_graph.get_explanation(edge_id);
std::cout << lit << "\n";
get_context().literal2expr(lit, tmp);
core.push_back(tmp);
}
}
blocker = mk_gt(v, r);
return inf_eps_rational<inf_rational>(rational(0), r);
}
default:
TRACE("opt", tout << "unbounded\n"; );
blocker = m.mk_false();
return inf_eps_rational<inf_rational>::infinity();
}
}
@ -1135,7 +1143,9 @@ expr_ref theory_diff_logic<Ext>::block_objective(theory_var v, inf_rational cons
}
else {
//
f = m.mk_true();
expr_ref_vector const& core = m_objective_assignments[v];
f = m.mk_not(m.mk_and(core.size(), core.c_ptr()));
TRACE("arith", tout << "block: " << f << "\n";);
return f;
}
@ -1152,8 +1162,10 @@ expr_ref theory_diff_logic<Ext>::block_objective(theory_var v, inf_rational cons
}
template<typename Ext>
expr* theory_diff_logic<Ext>::mk_gt(theory_var v, inf_rational const& val) {
expr_ref theory_diff_logic<Ext>::mk_gt(theory_var v, inf_rational const& val) {
expr_ref o = block_objective(v, val);
return o;
#if 0
context & ctx = get_context();
model_ref mdl;
ctx.get_model(mdl);
@ -1162,6 +1174,7 @@ expr* theory_diff_logic<Ext>::mk_gt(theory_var v, inf_rational const& val) {
model_implicant impl_extractor(m);
expr_ref_vector implicants = impl_extractor.minimize_literals(formulas, mdl);
return m.mk_and(o, m.mk_not(m.mk_and(implicants.size(), implicants.c_ptr())));
#endif
}
template<typename Ext>

View file

@ -29,9 +29,8 @@ namespace smt {
class theory_opt {
public:
typedef inf_eps_rational<inf_rational> inf_eps;
virtual inf_eps maximize(theory_var v) { UNREACHABLE(); return inf_eps::infinity(); }
virtual inf_eps maximize(theory_var v, expr_ref& blocker) = 0; // { UNREACHABLE(); return inf_eps::infinity(); }
virtual theory_var add_objective(app* term) { UNREACHABLE(); return null_theory_var; }
virtual expr* mk_gt(theory_var v, inf_rational const& val) { UNREACHABLE(); return 0; }
virtual expr* mk_ge(filter_model_converter& fm, theory_var v, inf_eps const& val) { UNREACHABLE(); return 0; }
};
}