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fixing lex optimization

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2013-12-13 23:36:42 +01:00
parent df5c2adc4e
commit 8c85ee6b7c
13 changed files with 219 additions and 125 deletions
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107
src/opt/opt_context.cpp
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@ -28,6 +28,7 @@ Notes:
#include "lia2card_tactic.h"
#include "elim01_tactic.h"
#include "tactical.h"
#include "model_smt2_pp.h"
namespace opt {
@ -85,12 +86,13 @@ namespace opt {
return is_sat;
}
s.get_model(m_model);
m_optsmt.setup(s);
update_lower();
switch (m_objectives.size()) {
case 0:
return is_sat;
case 1:
return execute(m_objectives[0], false);
return execute(m_objectives[0], true);
default: {
opt_params optp(m_params);
symbol pri = optp.priority();
@ -111,19 +113,17 @@ namespace opt {
mdl = m_model;
if (m_model_converter) {
(*m_model_converter)(mdl, 0);
get_solver().mc()(mdl, 0);
}
}
lbool context::execute_min_max(unsigned index, bool committed, bool is_max) {
// HACK: reuse m_optsmt without regard for box reuse and not considering
// use-case of lex.
lbool result = m_optsmt(get_solver());
lbool context::execute_min_max(unsigned index, bool committed) {
lbool result = m_optsmt.lex(index);
if (result == l_true) m_optsmt.get_model(m_model);
if (committed) m_optsmt.commit_assignment(index);
return result;
}
lbool context::execute_maxsat(symbol const& id, bool committed) {
maxsmt& ms = *m_maxsmts.find(id);
lbool result = ms(get_solver());
@ -134,8 +134,8 @@ namespace opt {
lbool context::execute(objective const& obj, bool committed) {
switch(obj.m_type) {
case O_MAXIMIZE: return execute_min_max(obj.m_index, committed, true);
case O_MINIMIZE: return execute_min_max(obj.m_index, committed, false);
case O_MAXIMIZE: return execute_min_max(obj.m_index, committed);
case O_MINIMIZE: return execute_min_max(obj.m_index, committed);
case O_MAXSMT: return execute_maxsat(obj.m_id, committed);
default: UNREACHABLE(); return l_undef;
}
@ -145,16 +145,23 @@ namespace opt {
lbool r = l_true;
for (unsigned i = 0; r == l_true && i < m_objectives.size(); ++i) {
r = execute(m_objectives[i], i + 1 < m_objectives.size());
if (r == l_true && !get_lower_as_num(i).is_finite()) {
return r;
}
}
DEBUG_CODE(if (r == l_true) validate_lex(););
return r;
}
lbool context::execute_box() {
lbool r = l_true;
lbool r = m_optsmt.box();
for (unsigned i = 0; r == l_true && i < m_objectives.size(); ++i) {
get_solver().push();
r = execute(m_objectives[i], false);
get_solver().pop(1);
objective const& obj = m_objectives[i];
if (obj.m_type == O_MAXSMT) {
get_solver().push();
r = execute(obj, false);
get_solver().pop(1);
}
}
return r;
}
@ -244,7 +251,9 @@ namespace opt {
terms[i] = m.mk_not(terms[i].get());
}
}
id = symbol(index);
std::ostringstream out;
out << term;
id = symbol(out.str().c_str());
return true;
}
if (is_maximize(fml, term, index) &&
@ -266,7 +275,9 @@ namespace opt {
offset += weights[i];
}
neg = true;
id = symbol(index);
std::ostringstream out;
out << term;
id = symbol(out.str().c_str());
return true;
}
return false;
@ -426,17 +437,15 @@ namespace opt {
for (unsigned i = 0; i < m_objectives.size(); ++i) {
objective const& obj = m_objectives[i];
display_objective(out, obj);
out << "|-> " << get_upper(i) << "\n";
if (get_lower_as_num(i) != get_upper_as_num(i)) {
out << " |-> [" << get_lower(i) << ":" << get_upper(i) << "]\n";
}
else {
out << "|-> " << get_lower(i) << "\n";
}
}
}
void context::display_range_assignment(std::ostream& out) {
for (unsigned i = 0; i < m_objectives.size(); ++i) {
objective const& obj = m_objectives[i];
display_objective(out, obj);
out << " |-> [" << get_lower(i) << ":" << get_upper(i) << "]\n";
}
}
void context::display_objective(std::ostream& out, objective const& obj) const {
switch(obj.m_type) {
@ -453,8 +462,7 @@ namespace opt {
}
}
expr_ref context::get_lower(unsigned idx) {
inf_eps context::get_lower_as_num(unsigned idx) {
if (idx > m_objectives.size()) {
throw default_exception("index out of bounds");
}
@ -464,18 +472,19 @@ namespace opt {
rational r = m_maxsmts.find(obj.m_id)->get_lower();
if (obj.m_neg) r.neg();
r += obj.m_offset;
return to_expr(inf_eps(r));
return inf_eps(r);
}
case O_MINIMIZE:
case O_MAXIMIZE:
return to_expr(m_optsmt.get_lower(obj.m_index));
return m_optsmt.get_lower(obj.m_index);
default:
UNREACHABLE();
return expr_ref(m);
}
return inf_eps();
}
}
expr_ref context::get_upper(unsigned idx) {
inf_eps context::get_upper_as_num(unsigned idx) {
if (idx > m_objectives.size()) {
throw default_exception("index out of bounds");
}
@ -485,17 +494,25 @@ namespace opt {
rational r = m_maxsmts.find(obj.m_id)->get_upper();
if (obj.m_neg) r.neg();
r += obj.m_offset;
return to_expr(inf_eps(r));
return inf_eps(r);
}
case O_MINIMIZE:
case O_MAXIMIZE:
return to_expr(m_optsmt.get_upper(obj.m_index));
return m_optsmt.get_upper(obj.m_index);
default:
UNREACHABLE();
return expr_ref(m);
return inf_eps();
}
}
expr_ref context::get_lower(unsigned idx) {
return to_expr(get_lower_as_num(idx));
}
expr_ref context::get_upper(unsigned idx) {
return to_expr(get_upper_as_num(idx));
}
expr_ref context::to_expr(inf_eps const& n) {
rational inf = n.get_infinity();
rational r = n.get_rational();
@ -676,4 +693,30 @@ namespace opt {
return out.str();
}
void context::validate_lex() {
arith_util a(m);
rational r1;
expr_ref val(m);
for (unsigned i = 0; i < m_objectives.size(); ++i) {
objective const& obj = m_objectives[i];
switch(obj.m_type) {
case O_MINIMIZE:
case O_MAXIMIZE: {
inf_eps n = m_optsmt.get_lower(obj.m_index);
if (n.get_infinity().is_zero() &&
n.get_infinitesimal().is_zero() &&
m_model->eval(obj.m_term, val) &&
a.is_numeral(val, r1)) {
rational r2 = n.get_rational();
CTRACE("opt", r1 != r2, tout << obj.m_term << " evaluates to " << r1 << " but has objective " << r2 << "\n";);
CTRACE("opt", r1 != r2, model_smt2_pp(tout, m, *m_model, 0););
SASSERT(r1 == r2);
}
break;
}
case O_MAXSMT:
break;
}
}
}
}