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fix local search encoding bug

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2018-02-08 07:27:32 -08:00
parent 615e1e0845
commit 5e482def18
8 changed files with 78 additions and 63 deletions

View file

@ -721,8 +721,8 @@ namespace opt {
}
goal_ref g(alloc(goal, m, true, false));
for (unsigned i = 0; i < fmls.size(); ++i) {
g->assert_expr(fmls[i].get());
for (expr* fml : fmls) {
g->assert_expr(fml);
}
tactic_ref tac0 =
and_then(mk_simplify_tactic(m, m_params),

View file

@ -453,7 +453,6 @@ namespace sat {
bool validate_resolvent();
void display(std::ostream& out, ineq& p, bool values = false) const;
void display(std::ostream& out, constraint const& c, bool values) const;
void display(std::ostream& out, card const& c, bool values) const;
void display(std::ostream& out, pb const& p, bool values) const;
void display(std::ostream& out, xr const& c, bool values) const;
@ -500,6 +499,7 @@ namespace sat {
virtual bool is_blocked(literal l, ext_constraint_idx idx);
ptr_vector<constraint> const & constraints() const { return m_constraints; }
void display(std::ostream& out, constraint const& c, bool values) const;
virtual bool validate();

View file

@ -104,7 +104,7 @@ namespace sat {
coeff_vector& falsep = m_vars[v].m_watch[!is_true];
for (unsigned i = 0; i < falsep.size(); ++i) {
constraint& c = m_constraints[falsep[i].m_constraint_id];
SASSERT(falsep[i].m_coeff == 1);
//SASSERT(falsep[i].m_coeff == 1);
// will --slack
if (c.m_slack <= 0) {
dec_slack_score(v);
@ -113,7 +113,7 @@ namespace sat {
}
}
for (unsigned i = 0; i < truep.size(); ++i) {
SASSERT(truep[i].m_coeff == 1);
//SASSERT(truep[i].m_coeff == 1);
constraint& c = m_constraints[truep[i].m_constraint_id];
// will --true_terms_count[c]
// will ++slack
@ -139,7 +139,8 @@ namespace sat {
void local_search::reinit() {
if (!m_is_pb) {
IF_VERBOSE(10, verbose_stream() << "(sat-local-search reinit)\n";);
if (true || !m_is_pb) {
//
// the following methods does NOT converge for pseudo-boolean
// can try other way to define "worse" and "better"
@ -156,8 +157,7 @@ namespace sat {
}
}
for (unsigned i = 0; i < m_constraints.size(); ++i) {
constraint& c = m_constraints[i];
for (constraint & c : m_constraints) {
c.m_slack = c.m_k;
}
@ -216,31 +216,43 @@ namespace sat {
}
void local_search::verify_solution() const {
for (unsigned i = 0; i < m_constraints.size(); ++i) {
verify_constraint(m_constraints[i]);
}
for (constraint const& c : m_constraints)
verify_constraint(c);
}
void local_search::verify_unsat_stack() const {
for (unsigned i = 0; i < m_unsat_stack.size(); ++i) {
constraint const& c = m_constraints[m_unsat_stack[i]];
void local_search::verify_unsat_stack() const {
for (unsigned i : m_unsat_stack) {
constraint const& c = m_constraints[i];
SASSERT(c.m_k < constraint_value(c));
}
}
unsigned local_search::constraint_coeff(constraint const& c, literal l) const {
for (auto const& pb : m_vars[l.var()].m_watch[is_pos(l)]) {
if (pb.m_constraint_id == c.m_id) return pb.m_coeff;
}
UNREACHABLE();
return 0;
}
unsigned local_search::constraint_value(constraint const& c) const {
unsigned value = 0;
for (unsigned i = 0; i < c.size(); ++i) {
value += is_true(c[i]) ? 1 : 0;
literal t = c[i];
if (is_true(t)) {
value += constraint_coeff(c, t);
}
}
return value;
}
void local_search::verify_constraint(constraint const& c) const {
unsigned value = constraint_value(c);
IF_VERBOSE(11, display(verbose_stream() << "verify ", c););
TRACE("sat", display(verbose_stream() << "verify ", c););
if (c.m_k < value) {
IF_VERBOSE(0, display(verbose_stream() << "violated constraint: ", c);
verbose_stream() << "value: " << value << "\n";);
IF_VERBOSE(0, display(verbose_stream() << "violated constraint: ", c) << "value: " << value << "\n";);
UNREACHABLE();
}
}
@ -252,7 +264,7 @@ namespace sat {
// ~c <= k
void local_search::add_cardinality(unsigned sz, literal const* c, unsigned k) {
unsigned id = m_constraints.size();
m_constraints.push_back(constraint(k));
m_constraints.push_back(constraint(k, id));
for (unsigned i = 0; i < sz; ++i) {
m_vars.reserve(c[i].var() + 1);
literal t(~c[i]);
@ -264,14 +276,15 @@ namespace sat {
}
}
// c * coeffs <= k
void local_search::add_pb(unsigned sz, literal const* c, unsigned const* coeffs, unsigned k) {
unsigned id = m_constraints.size();
m_constraints.push_back(constraint(k));
m_constraints.push_back(constraint(k, id));
for (unsigned i = 0; i < sz; ++i) {
m_vars.reserve(c[i].var() + 1);
literal t(~c[i]);
literal t(c[i]);
m_vars[t.var()].m_watch[is_pos(t)].push_back(pbcoeff(id, coeffs[i]));
m_constraints.back().push(t); // add coefficient to constraint?
m_constraints.back().push(t);
}
if (sz == 1 && k == 0) {
m_vars[c[0].var()].m_bias = c[0].sign() ? 0 : 100;
@ -359,7 +372,7 @@ namespace sat {
lits.reset();
coeffs.reset();
for (unsigned j = 0; j < n; ++j) lits.push_back(~c[j]), coeffs.push_back(1);
for (literal l : c) lits.push_back(~l), coeffs.push_back(1);
lits.push_back(c.lit()); coeffs.push_back(k);
add_pb(lits.size(), lits.c_ptr(), coeffs.c_ptr(), n);
}
@ -889,21 +902,27 @@ namespace sat {
}
}
void local_search::display(std::ostream& out) const {
std::ostream& local_search::display(std::ostream& out) const {
for (constraint const& c : m_constraints) {
display(out, c);
}
for (bool_var v = 0; v < num_vars(); ++v) {
display(out, v, m_vars[v]);
}
return out;
}
void local_search::display(std::ostream& out, constraint const& c) const {
out << c.m_literals << " <= " << c.m_k << " lhs value: " << constraint_value(c) << "\n";
std::ostream& local_search::display(std::ostream& out, constraint const& c) const {
for (literal l : c) {
unsigned coeff = constraint_coeff(c, l);
if (coeff > 1) out << coeff << " * ";
out << l << " ";
}
return out << " <= " << c.m_k << " lhs value: " << constraint_value(c) << "\n";
}
void local_search::display(std::ostream& out, unsigned v, var_info const& vi) const {
out << "v" << v << " := " << (vi.m_value?"true":"false") << " bias: " << vi.m_bias << "\n";
std::ostream& local_search::display(std::ostream& out, unsigned v, var_info const& vi) const {
return out << "v" << v << " := " << (vi.m_value?"true":"false") << " bias: " << vi.m_bias << "\n";
}
bool local_search::check_goodvar() {

View file

@ -99,11 +99,12 @@ namespace sat {
};
struct constraint {
unsigned m_id;
unsigned m_k;
int m_slack;
unsigned m_size;
literal_vector m_literals;
constraint(unsigned k) : m_k(k), m_slack(0), m_size(0) {}
constraint(unsigned k, unsigned id) : m_id(id), m_k(k), m_slack(0), m_size(0) {}
void push(literal l) { m_literals.push_back(l); ++m_size; }
unsigned size() const { return m_size; }
literal const& operator[](unsigned idx) const { return m_literals[idx]; }
@ -232,6 +233,8 @@ namespace sat {
unsigned constraint_value(constraint const& c) const;
unsigned constraint_coeff(constraint const& c, literal l) const;
void print_info(std::ostream& out);
void extract_model();
@ -240,11 +243,11 @@ namespace sat {
void add_clause(unsigned sz, literal const* c);
void display(std::ostream& out) const;
std::ostream& display(std::ostream& out) const;
void display(std::ostream& out, constraint const& c) const;
std::ostream& display(std::ostream& out, constraint const& c) const;
void display(std::ostream& out, unsigned v, var_info const& vi) const;
std::ostream& display(std::ostream& out, unsigned v, var_info const& vi) const;
public:

View file

@ -517,7 +517,10 @@ struct goal2sat::imp {
mk_clause(~l1, ~l2, l);
m_result_stack.shrink(m_result_stack.size() - t->get_num_args());
m_result_stack.push_back(sign ? ~l : l);
if (root) mk_clause(~l);
if (root) {
m_result_stack.reset();
mk_clause(~l);
}
}
}
@ -586,7 +589,10 @@ struct goal2sat::imp {
mk_clause(~l1, ~l2, l);
m_result_stack.shrink(m_result_stack.size() - t->get_num_args());
m_result_stack.push_back(sign ? ~l : l);
if (root) mk_clause(~l);
if (root) {
mk_clause(~l);
m_result_stack.reset();
}
}
}
@ -808,7 +814,7 @@ struct goal2sat::imp {
}
f = m.mk_or(fmls.size(), fmls.c_ptr());
}
TRACE("goal2sat", tout << mk_pp(f, m) << "\n";);
TRACE("goal2sat", tout << f << "\n";);
process(f);
skip_dep:
;

View file

@ -10,6 +10,7 @@ Copyright (c) 2015 Microsoft Corporation
#include "opt/opt_context.h"
#include "ast/ast_util.h"
#include "ast/arith_decl_plugin.h"
#include "ast/ast_pp.h"
#include "util/gparams.h"
#include "util/timeout.h"
#include "ast/reg_decl_plugins.h"
@ -99,21 +100,20 @@ static unsigned parse_opt(std::istream& in, opt_format f) {
case l_false: std::cout << "unsat\n"; break;
case l_undef: std::cout << "unknown\n"; break;
}
DEBUG_CODE(
if (false && r == l_true) {
model_ref mdl;
opt.get_model(mdl);
expr_ref_vector hard(m);
opt.get_hard_constraints(hard);
for (unsigned i = 0; i < hard.size(); ++i) {
std::cout << "validate: " << i << "\n";
expr_ref tmp(m);
VERIFY(mdl->eval(hard[i].get(), tmp));
if (!m.is_true(tmp)) {
std::cout << tmp << "\n";
}
if (r != l_false && gparams::get().get_bool("model_validate", false)) {
model_ref mdl;
opt.get_model(mdl);
expr_ref_vector hard(m);
opt.get_hard_constraints(hard);
for (expr* h : hard) {
expr_ref tmp(m);
VERIFY(mdl->eval(h, tmp));
if (!m.is_true(tmp)) {
std::cout << mk_pp(h, m) << " " << tmp << "\n";
}
});
}
}
}
catch (z3_exception & ex) {
std::cerr << ex.msg() << "\n";

View file

@ -213,7 +213,9 @@ public:
new_pr = m.mk_rewrite(g->form(i), new_curr);
new_pr = m.mk_modus_ponens(g->pr(i), new_pr);
}
// IF_VERBOSE(0, verbose_stream() << mk_pp(g->form(i), m) << "\n--->\n" << new_curr << "\n";);
g->update(i, new_curr, new_pr, g->dep(i));
}
for (expr* a : axioms) {
g->assert_expr(a);

View file

@ -53,21 +53,6 @@ void generic_model_converter::operator()(model_ref & md) {
break;
case instruction::ADD:
ev(e.m_def, val);
if (e.m_f->get_name() == symbol("FOX-PIT-17")) {
IF_VERBOSE(0, verbose_stream() << e.m_f->get_name() << " " << e.m_def << " -> " << val << "\n";);
ptr_vector<expr> ts;
ts.push_back(e.m_def);
while (!ts.empty()) {
app* t = to_app(ts.back());
ts.pop_back();
if (t->get_num_args() > 0) {
ts.append(t->get_num_args(), t->get_args());
}
expr_ref tmp(m);
ev(t, tmp);
IF_VERBOSE(0, verbose_stream() << mk_pp(t, m) << " -> " << tmp << "\n";);
}
}
TRACE("model_converter", tout << e.m_f->get_name() << " ->\n" << e.m_def << "\n==>\n" << val << "\n";);
arity = e.m_f->get_arity();
reset_ev = false;