z3-z3-4.13.0.src.sat.sat_solver.inc_sat_solver.cpp Maven / Gradle / Ivy
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/*++
Copyright (c) 2014 Microsoft Corporation
Module Name:
inc_sat_solver.cpp
Abstract:
incremental solver based on SAT core.
Author:
Nikolaj Bjorner (nbjorner) 2014-7-30
Notes:
--*/
#include "util/gparams.h"
#include "util/stacked_value.h"
#include "ast/ast_pp.h"
#include "ast/ast_translation.h"
#include "ast/ast_util.h"
#include "solver/solver.h"
#include "solver/tactic2solver.h"
#include "solver/parallel_params.hpp"
#include "solver/parallel_tactical.h"
#include "tactic/tactical.h"
#include "tactic/aig/aig_tactic.h"
#include "tactic/core/propagate_values_tactic.h"
#include "tactic/bv/max_bv_sharing_tactic.h"
#include "tactic/arith/card2bv_tactic.h"
#include "tactic/bv/bit_blaster_tactic.h"
#include "tactic/core/simplify_tactic.h"
#include "tactic/bv/bit_blaster_model_converter.h"
#include "model/model_smt2_pp.h"
#include "model/model_v2_pp.h"
#include "model/model_evaluator.h"
#include "sat/sat_solver.h"
#include "sat/sat_params.hpp"
#include "sat/smt/euf_solver.h"
#include "sat/tactic/goal2sat.h"
#include "sat/tactic/sat2goal.h"
#include "sat/tactic/sat_tactic.h"
#include "sat/sat_simplifier_params.hpp"
// incremental SAT solver.
class inc_sat_solver : public solver {
mutable sat::solver m_solver;
stacked_value m_has_uninterpreted;
goal2sat m_goal2sat;
params_ref m_params;
expr_ref_vector m_fmls;
expr_ref_vector m_asmsf;
unsigned_vector m_fmls_lim;
unsigned_vector m_asms_lim;
unsigned_vector m_fmls_head_lim;
unsigned m_fmls_head;
expr_ref_vector m_core;
atom2bool_var m_map;
scoped_ptr m_bb_rewriter;
tactic_ref m_preprocess;
bool m_is_cnf;
unsigned m_num_scopes;
sat::literal_vector m_asms;
goal_ref_buffer m_subgoals;
proof_converter_ref m_pc;
sref_vector m_mcs;
mutable model_converter_ref m_mc0; // TBD: should be saved/retained under push/pop
mutable obj_hashtable m_inserted_const2bits;
mutable ref m_sat_mc;
mutable model_converter_ref m_cached_mc;
svector m_weights;
std::string m_unknown;
// access formulas after they have been pre-processed and handled by the sat solver.
// this allows to access the internal state of the SAT solver and carry on partial results.
bool m_internalized_converted; // have internalized formulas been converted back
expr_ref_vector m_internalized_fmls; // formulas in internalized format
typedef obj_map dep2asm_t;
dep2asm_t m_dep2asm;
bool is_internalized() const { return m_fmls_head == m_fmls.size(); }
public:
inc_sat_solver(ast_manager& m, params_ref const& p, bool incremental_mode):
solver(m),
m_solver(p, m.limit()),
m_has_uninterpreted(false),
m_fmls(m),
m_asmsf(m),
m_fmls_head(0),
m_core(m),
m_map(m),
m_is_cnf(true),
m_num_scopes(0),
m_unknown("no reason given"),
m_internalized_converted(false),
m_internalized_fmls(m) {
updt_params(p);
m_mcs.push_back(nullptr);
init_preprocess();
m_solver.set_incremental(incremental_mode && !override_incremental());
}
bool override_incremental() const {
sat_simplifier_params p(m_params);
return p.override_incremental();
}
bool is_incremental() const {
return m_solver.get_config().m_incremental;
}
solver* translate(ast_manager& dst_m, params_ref const& p) override {
ast_translation tr(m, dst_m);
m_solver.pop_to_base_level();
inc_sat_solver* result = alloc(inc_sat_solver, dst_m, p, is_incremental());
auto* ext = get_euf();
if (ext) {
auto& si = result->m_goal2sat.si(dst_m, m_params, result->m_solver, result->m_map, result->m_dep2asm, is_incremental());
euf::solver::scoped_set_translate st(*ext, dst_m, si);
result->m_solver.copy(m_solver);
}
else {
result->m_solver.copy(m_solver);
}
result->m_fmls_head = m_fmls_head;
for (expr* f : m_fmls) result->m_fmls.push_back(tr(f));
for (expr* f : m_asmsf) result->m_asmsf.push_back(tr(f));
for (auto & kv : m_map) result->m_map.insert(tr(kv.m_key), kv.m_value);
for (unsigned l : m_fmls_lim) result->m_fmls_lim.push_back(l);
for (unsigned a : m_asms_lim) result->m_asms_lim.push_back(a);
for (unsigned h : m_fmls_head_lim) result->m_fmls_head_lim.push_back(h);
for (expr* f : m_internalized_fmls) result->m_internalized_fmls.push_back(tr(f));
if (m_mcs.back()) result->m_mcs.push_back(m_mcs.back()->translate(tr));
if (m_sat_mc) result->m_sat_mc = dynamic_cast(m_sat_mc->translate(tr));
result->m_has_uninterpreted = m_has_uninterpreted;
// copy m_bb_rewriter?
result->m_internalized_converted = m_internalized_converted;
return result;
}
void set_progress_callback(progress_callback * callback) override {}
void display_weighted(std::ostream& out, unsigned sz, expr * const * assumptions, unsigned const* weights) {
if (weights != nullptr) {
for (unsigned i = 0; i < sz; ++i) m_weights.push_back(weights[i]);
}
init_preprocess();
m_solver.pop_to_base_level();
m_dep2asm.reset();
expr_ref_vector asms(m);
for (unsigned i = 0; i < sz; ++i) {
expr_ref a(m.mk_fresh_const("s", m.mk_bool_sort()), m);
expr_ref fml(m.mk_implies(a, assumptions[i]), m);
assert_expr(fml);
asms.push_back(a);
}
VERIFY(l_true == internalize_formulas());
VERIFY(l_true == internalize_assumptions(sz, asms.data()));
svector nweights;
for (unsigned i = 0; i < m_asms.size(); ++i) {
nweights.push_back((unsigned) m_weights[i]);
}
m_weights.reset();
m_solver.display_wcnf(out, m_asms.size(), m_asms.data(), nweights.data());
}
bool is_literal(expr* e) const {
return
is_uninterp_const(e) ||
(m.is_not(e, e) && is_uninterp_const(e));
}
lbool check_sat_core(unsigned sz, expr * const * assumptions) override {
m_solver.pop_to_base_level();
m_core.reset();
if (m_solver.inconsistent()) return l_false;
expr_ref_vector _assumptions(m);
obj_map asm2fml;
for (unsigned i = 0; i < sz; ++i) {
if (!is_literal(assumptions[i])) {
expr_ref a(m.mk_fresh_const("s", m.mk_bool_sort()), m);
expr_ref fml(m.mk_eq(a, assumptions[i]), m);
assert_expr(fml);
_assumptions.push_back(a);
asm2fml.insert(a, assumptions[i]);
}
else {
_assumptions.push_back(assumptions[i]);
asm2fml.insert(assumptions[i], assumptions[i]);
}
}
TRACE("sat", tout << _assumptions << "\n";);
m_dep2asm.reset();
lbool r = internalize_formulas();
if (r != l_true) return r;
r = internalize_assumptions(sz, _assumptions.data());
if (r != l_true) return r;
init_reason_unknown();
m_internalized_converted = false;
bool reason_set = false;
try {
// IF_VERBOSE(0, m_solver.display(verbose_stream()));
r = m_solver.check(m_asms.size(), m_asms.data());
}
catch (z3_exception& ex) {
IF_VERBOSE(1, verbose_stream() << "exception: " << ex.msg() << "\n";);
if (m.inc()) {
reason_set = true;
set_reason_unknown(std::string("(sat.giveup ") + ex.msg() + ')');
}
r = l_undef;
}
switch (r) {
case l_true:
if (m_has_uninterpreted()) {
set_reason_unknown("(sat.giveup has-uninterpreted)");
r = l_undef;
}
else if (sz > 0) {
check_assumptions();
}
break;
case l_false:
// TBD: expr_dependency core is not accounted for.
if (!m_asms.empty()) {
extract_core(asm2fml);
}
break;
default:
if (!reason_set) {
set_reason_unknown(m_solver.get_reason_unknown());
}
break;
}
return r;
}
void push() override {
try {
internalize_formulas();
}
catch (...) {
push_internal();
throw;
}
push_internal();
}
void push_internal() {
m_goal2sat.user_push();
m_solver.user_push();
++m_num_scopes;
m_mcs.push_back(m_mcs.back());
m_fmls_lim.push_back(m_fmls.size());
m_asms_lim.push_back(m_asmsf.size());
m_fmls_head_lim.push_back(m_fmls_head);
if (m_bb_rewriter) m_bb_rewriter->push();
m_map.push();
m_has_uninterpreted.push();
}
void pop(unsigned n) override {
if (n > m_num_scopes) { // allow inc_sat_solver to
n = m_num_scopes; // take over for another solver.
}
if (m_bb_rewriter) m_bb_rewriter->pop(n);
m_inserted_const2bits.reset();
m_map.pop(n);
SASSERT(n <= m_num_scopes);
m_goal2sat.user_pop(n);
m_solver.user_pop(n);
m_num_scopes -= n;
// ? m_internalized_converted = false;
m_has_uninterpreted.pop(n);
while (n > 0) {
m_mcs.pop_back();
m_fmls_head = m_fmls_head_lim.back();
m_fmls.resize(m_fmls_lim.back());
m_fmls_lim.pop_back();
m_fmls_head_lim.pop_back();
m_asmsf.resize(m_asms_lim.back());
m_asms_lim.pop_back();
--n;
}
}
void set_phase(expr* e) override {
bool is_not = m.is_not(e, e);
sat::bool_var b = m_map.to_bool_var(e);
if (b != sat::null_bool_var)
m_solver.set_phase(sat::literal(b, is_not));
}
class sat_phase : public phase, public sat::literal_vector {};
phase* get_phase() override {
sat_phase* p = alloc(sat_phase);
for (unsigned v = m_solver.num_vars(); v-- > 0; ) {
p->push_back(sat::literal(v, !m_solver.get_phase(v)));
}
return p;
}
void set_phase(phase* p) override {
for (auto lit : *static_cast(p))
m_solver.set_phase(lit);
}
void move_to_front(expr* e) override {
m.is_not(e, e);
sat::bool_var b = m_map.to_bool_var(e);
if (b != sat::null_bool_var)
m_solver.move_to_front(b);
}
unsigned get_scope_level() const override {
return m_num_scopes;
}
void assert_expr_core2(expr * t, expr * a) override {
if (a) {
m_asmsf.push_back(a);
if (m_is_cnf && is_literal(t) && is_literal(a)) {
assert_expr_core(m.mk_or(::mk_not(m, a), t));
}
else if (m_is_cnf && m.is_or(t) && is_clause(t) && is_literal(a)) {
expr_ref_vector args(m);
args.push_back(::mk_not(m, a));
args.append(to_app(t)->get_num_args(), to_app(t)->get_args());
assert_expr_core(m.mk_or(args.size(), args.data()));
}
else {
m_is_cnf = false;
assert_expr_core(m.mk_implies(a, t));
}
}
else {
assert_expr_core(t);
}
}
ast_manager& get_manager() const override { return m; }
void assert_expr_core(expr * t) override {
TRACE("goal2sat", tout << mk_pp(t, m) << "\n";);
m_is_cnf &= is_clause(t);
m_fmls.push_back(t);
}
void set_produce_models(bool f) override {}
void collect_param_descrs(param_descrs & r) override {
solver::collect_param_descrs(r);
goal2sat::collect_param_descrs(r);
sat::solver::collect_param_descrs(r);
}
void updt_params(params_ref const & p) override {
m_params.append(p);
sat_params p1(p);
m_params.set_bool("keep_cardinality_constraints", p1.cardinality_solver());
m_params.set_sym("pb.solver", p1.pb_solver());
m_solver.updt_params(m_params);
m_solver.set_incremental(is_incremental() && !override_incremental());
if (p1.euf() && !get_euf())
ensure_euf();
}
void collect_statistics(statistics & st) const override {
if (m_preprocess) m_preprocess->collect_statistics(st);
m_solver.collect_statistics(st);
}
void get_unsat_core(expr_ref_vector & r) override {
r.reset();
r.append(m_core.size(), m_core.data());
}
void get_levels(ptr_vector const& vars, unsigned_vector& depth) override {
unsigned sz = vars.size();
depth.resize(sz);
for (unsigned i = 0; i < sz; ++i) {
auto bv = m_map.to_bool_var(vars[i]);
depth[i] = bv == sat::null_bool_var ? UINT_MAX : m_solver.lvl(bv);
}
}
expr_ref_vector get_trail(unsigned max_level) override {
expr_ref_vector result(m);
unsigned sz = m_solver.trail_size();
expr_ref_vector lit2expr(m);
lit2expr.resize(m_solver.num_vars() * 2);
m_map.mk_inv(lit2expr);
for (unsigned i = 0; i < sz; ++i) {
sat::literal lit = m_solver.trail_literal(i);
if (m_solver.lvl(lit) > max_level)
continue;
expr_ref e(lit2expr.get(lit.index()), m);
if (e)
result.push_back(e);
}
return result;
}
proof * get_proof_core() override {
return nullptr;
}
expr_ref_vector last_cube(bool is_sat) {
expr_ref_vector result(m);
result.push_back(is_sat ? m.mk_true() : m.mk_false());
return result;
}
expr_ref_vector cube(expr_ref_vector& vs, unsigned backtrack_level) override {
if (!is_internalized()) {
lbool r = internalize_formulas();
if (r != l_true) {
IF_VERBOSE(0, verbose_stream() << "internalize produced " << r << "\n");
return expr_ref_vector(m);
}
}
convert_internalized();
if (m_solver.inconsistent())
return last_cube(false);
obj_hashtable _vs;
for (expr* v : vs) _vs.insert(v);
sat::bool_var_vector vars;
for (auto& kv : m_map) {
if (_vs.empty() || _vs.contains(kv.m_key))
vars.push_back(kv.m_value);
}
sat::literal_vector lits;
lbool result = m_solver.cube(vars, lits, backtrack_level);
expr_ref_vector fmls(m);
expr_ref_vector lit2expr(m);
lit2expr.resize(m_solver.num_vars() * 2);
m_map.mk_inv(lit2expr);
for (sat::literal l : lits) {
expr* e = lit2expr.get(l.index());
SASSERT(e);
fmls.push_back(e);
}
vs.reset();
for (sat::bool_var v : vars) {
expr* x = lit2expr[sat::literal(v, false).index()].get();
if (x) {
vs.push_back(x);
}
}
switch (result) {
case l_true:
return last_cube(true);
case l_false:
return last_cube(false);
default:
break;
}
if (lits.empty()) {
set_reason_unknown(m_solver.get_reason_unknown());
}
return fmls;
}
expr* congruence_next(expr* e) override { return e; }
expr* congruence_root(expr* e) override { return e; }
lbool get_consequences_core(expr_ref_vector const& assumptions, expr_ref_vector const& vars, expr_ref_vector& conseq) override {
init_preprocess();
TRACE("sat", tout << assumptions << "\n" << vars << "\n";);
sat::literal_vector asms;
sat::bool_var_vector bvars;
vector lconseq;
m_dep2asm.reset();
obj_map asm2fml;
m_solver.pop_to_base_level();
lbool r = internalize_formulas();
if (r != l_true) return r;
r = internalize_vars(vars, bvars);
if (r != l_true) return r;
r = internalize_assumptions(assumptions.size(), assumptions.data());
if (r != l_true) return r;
r = m_solver.get_consequences(m_asms, bvars, lconseq);
if (r == l_false) {
if (!m_asms.empty()) {
extract_core(asm2fml);
}
return r;
}
// build map from bound variables to
// the consequences that cover them.
u_map bool_var2conseq;
for (unsigned i = 0; i < lconseq.size(); ++i) {
TRACE("sat", tout << lconseq[i] << "\n";);
bool_var2conseq.insert(lconseq[i][0].var(), i);
}
// extract original fixed variables
u_map asm2dep;
extract_asm2dep(asm2dep);
for (auto v : vars) {
expr_ref cons(m);
if (extract_fixed_variable(asm2dep, v, bool_var2conseq, lconseq, cons)) {
conseq.push_back(cons);
}
}
return r;
}
lbool find_mutexes(expr_ref_vector const& vars, vector& mutexes) override {
sat::literal_vector ls;
u_map lit2var;
for (unsigned i = 0; i < vars.size(); ++i) {
expr* e = vars[i];
bool neg = m.is_not(e, e);
sat::bool_var v = m_map.to_bool_var(e);
if (v != sat::null_bool_var) {
sat::literal lit(v, neg);
ls.push_back(lit);
lit2var.insert(lit.index(), vars[i]);
}
}
vector ls_mutexes;
m_solver.find_mutexes(ls, ls_mutexes);
for (sat::literal_vector const& ls_mutex : ls_mutexes) {
expr_ref_vector mutex(m);
for (sat::literal l : ls_mutex) {
mutex.push_back(lit2var.find(l.index()));
}
mutexes.push_back(mutex);
}
return l_true;
}
void init_reason_unknown() {
m_unknown = "no reason given";
}
std::string reason_unknown() const override {
return m_unknown;
}
void set_reason_unknown(char const* msg) override {
m_unknown = msg;
}
void set_reason_unknown(std::string &&msg) {
m_unknown = std::move(msg);
}
void get_labels(svector & r) override {
}
unsigned get_num_assertions() const override {
const_cast(this)->convert_internalized();
if (is_internalized() && m_internalized_converted) {
return m_internalized_fmls.size();
}
else {
return m_fmls.size();
}
}
expr * get_assertion(unsigned idx) const override {
if (is_internalized() && m_internalized_converted) {
return m_internalized_fmls[idx];
}
return m_fmls[idx];
}
unsigned get_num_assumptions() const override {
return m_asmsf.size();
}
expr * get_assumption(unsigned idx) const override {
return m_asmsf[idx];
}
model_converter_ref get_model_converter() const override {
const_cast(this)->convert_internalized();
if (m_cached_mc)
return m_cached_mc;
if (is_internalized() && m_internalized_converted) {
m_sat_mc->flush_smc(m_solver, m_map);
m_cached_mc = m_mcs.back();
m_cached_mc = concat(solver::get_model_converter().get(), m_cached_mc.get());
m_cached_mc = concat(m_cached_mc.get(), m_sat_mc.get());
TRACE("sat", m_cached_mc->display(tout););
return m_cached_mc;
}
else {
return solver::get_model_converter();
}
}
void convert_internalized() {
m_solver.pop_to_base_level();
if (!is_internalized() && m_fmls_head > 0)
internalize_formulas();
if (!is_internalized() || m_internalized_converted)
return;
sat2goal s2g;
m_cached_mc = nullptr;
goal g(m, false, true, false);
s2g(m_solver, m_map, m_params, g, m_sat_mc);
m_internalized_fmls.reset();
g.get_formulas(m_internalized_fmls);
TRACE("sat", m_solver.display(tout); tout << m_internalized_fmls << "\n";);
m_internalized_converted = true;
}
void init_preprocess() {
if (m_preprocess) {
m_preprocess->reset();
}
if (!m_bb_rewriter) {
m_bb_rewriter = alloc(bit_blaster_rewriter, m, m_params);
}
params_ref simp1_p = m_params;
simp1_p.set_bool("som", true);
simp1_p.set_bool("pull_cheap_ite", true);
simp1_p.set_bool("push_ite_bv", false);
simp1_p.set_bool("local_ctx", true);
simp1_p.set_uint("local_ctx_limit", 10000000);
simp1_p.set_bool("flat", true); // required by som
simp1_p.set_bool("hoist_mul", false); // required by som
simp1_p.set_bool("elim_and", true);
simp1_p.set_bool("blast_distinct", true);
params_ref simp2_p = m_params;
simp2_p.set_bool("flat", false);
sat_params sp(m_params);
if (sp.euf())
m_preprocess =
and_then(mk_simplify_tactic(m),
mk_propagate_values_tactic(m));
else
m_preprocess =
and_then(mk_simplify_tactic(m),
mk_propagate_values_tactic(m),
mk_card2bv_tactic(m, m_params), // updates model converter
using_params(mk_simplify_tactic(m), simp1_p),
mk_max_bv_sharing_tactic(m),
mk_bit_blaster_tactic(m, m_bb_rewriter.get()),
using_params(mk_simplify_tactic(m), simp2_p)
);
while (m_bb_rewriter->get_num_scopes() < m_num_scopes) {
m_bb_rewriter->push();
}
m_preprocess->reset();
}
euf::solver* get_euf() {
return dynamic_cast(m_solver.get_extension());
}
euf::solver* ensure_euf() {
m_goal2sat.init(m, m_params, m_solver, m_map, m_dep2asm, is_incremental());
auto* ext = m_goal2sat.ensure_euf();
return ext;
}
void register_on_clause(void* ctx, user_propagator::on_clause_eh_t& on_clause) override {
ensure_euf()->register_on_clause(ctx, on_clause);
}
void user_propagate_init(
void* ctx,
user_propagator::push_eh_t& push_eh,
user_propagator::pop_eh_t& pop_eh,
user_propagator::fresh_eh_t& fresh_eh) override {
ensure_euf()->user_propagate_init(ctx, push_eh, pop_eh, fresh_eh);
}
void user_propagate_register_fixed(user_propagator::fixed_eh_t& fixed_eh) override {
ensure_euf()->user_propagate_register_fixed(fixed_eh);
}
void user_propagate_register_final(user_propagator::final_eh_t& final_eh) override {
ensure_euf()->user_propagate_register_final(final_eh);
}
void user_propagate_register_eq(user_propagator::eq_eh_t& eq_eh) override {
ensure_euf()->user_propagate_register_eq(eq_eh);
}
void user_propagate_register_diseq(user_propagator::eq_eh_t& diseq_eh) override {
ensure_euf()->user_propagate_register_diseq(diseq_eh);
}
void user_propagate_register_expr(expr* e) override {
ensure_euf()->user_propagate_register_expr(e);
}
void user_propagate_register_created(user_propagator::created_eh_t& r) override {
ensure_euf()->user_propagate_register_created(r);
}
void user_propagate_register_decide(user_propagator::decide_eh_t& r) override {
ensure_euf()->user_propagate_register_decide(r);
}
private:
lbool check_uninterpreted() {
func_decl_ref_vector funs(m);
m_goal2sat.get_interpreted_funs(funs);
if (!funs.empty()) {
m_has_uninterpreted = true;
std::stringstream strm;
strm << "(sat.giveup interpreted functions sent to SAT solver " << funs <<")";
TRACE("sat", tout << strm.str() << "\n";);
IF_VERBOSE(1, verbose_stream() << strm.str() << "\n";);
set_reason_unknown(strm.str());
return l_undef;
}
return l_true;
}
lbool internalize_goal(unsigned sz, expr* const* fmls) {
m_solver.pop_to_base_level();
if (m_solver.inconsistent())
return l_false;
m_pc.reset();
m_goal2sat.init(m, m_params, m_solver, m_map, m_dep2asm, is_incremental());
m_goal2sat(sz, fmls);
if (!m_sat_mc) m_sat_mc = alloc(sat2goal::mc, m);
m_sat_mc->flush_smc(m_solver, m_map);
return check_uninterpreted();
}
lbool internalize_goal(goal_ref& g) {
m_solver.pop_to_base_level();
if (m_solver.inconsistent())
return l_false;
m_pc.reset();
m_subgoals.reset();
init_preprocess();
SASSERT(g->models_enabled());
if (g->proofs_enabled()) {
throw default_exception("generation of proof objects is not supported in this mode");
}
SASSERT(!g->proofs_enabled());
TRACE("sat", m_solver.display(tout); g->display(tout););
try {
if (m_is_cnf) {
m_subgoals.push_back(g.get());
}
else {
(*m_preprocess)(g, m_subgoals);
m_is_cnf = true;
}
}
catch (tactic_exception & ex) {
IF_VERBOSE(1, verbose_stream() << "exception in tactic " << ex.msg() << "\n";);
set_reason_unknown(ex.msg());
TRACE("sat", tout << "exception: " << ex.msg() << "\n";);
m_preprocess = nullptr;
m_bb_rewriter = nullptr;
return l_undef;
}
catch (...) {
m_preprocess = nullptr;
m_bb_rewriter = nullptr;
throw;
}
if (m_subgoals.size() != 1) {
IF_VERBOSE(0, verbose_stream() << "size of subgoals is not 1, it is: " << m_subgoals.size() << "\n");
return l_undef;
}
g = m_subgoals[0];
m_pc = g->pc();
m_mcs.set(m_mcs.size()-1, concat(m_mcs.back(), g->mc()));
TRACE("sat", g->display_with_dependencies(tout););
// ensure that if goal is already internalized, then import mc from m_solver.
m_goal2sat(*g, m_params, m_solver, m_map, m_dep2asm, is_incremental());
if (!m_sat_mc) m_sat_mc = alloc(sat2goal::mc, m);
m_sat_mc->flush_smc(m_solver, m_map);
return check_uninterpreted();
}
lbool internalize_assumptions(unsigned sz, expr* const* asms) {
if (sz == 0 && get_num_assumptions() == 0) {
m_asms.shrink(0);
return l_true;
}
for (unsigned i = 0; i < sz; ++i)
m_is_cnf &= is_literal(asms[i]);
for (unsigned i = 0; i < get_num_assumptions(); ++i)
m_is_cnf &= is_literal(get_assumption(i));
if (m_is_cnf) {
expr_ref_vector fmls(m);
fmls.append(sz, asms);
for (unsigned i = 0; i < get_num_assumptions(); ++i)
fmls.push_back(get_assumption(i));
m_goal2sat.init(m, m_params, m_solver, m_map, m_dep2asm, is_incremental());
m_goal2sat.assumptions(fmls.size(), fmls.data());
extract_assumptions(fmls.size(), fmls.data());
return l_true;
}
goal_ref g = alloc(goal, m, true, true); // models and cores are enabled.
for (unsigned i = 0; i < sz; ++i)
g->assert_expr(asms[i], m.mk_leaf(asms[i]));
for (unsigned i = 0; i < get_num_assumptions(); ++i)
g->assert_expr(get_assumption(i), m.mk_leaf(get_assumption(i)));
lbool res = internalize_goal(g);
if (res == l_true)
extract_assumptions(sz, asms);
return res;
}
lbool internalize_vars(expr_ref_vector const& vars, sat::bool_var_vector& bvars) {
for (expr* v : vars) {
internalize_var(v, bvars);
}
return l_true;
}
bool internalize_var(expr* v, sat::bool_var_vector& bvars) {
obj_map const2bits;
ptr_vector newbits;
m_bb_rewriter->get_translation(const2bits, newbits);
expr* bv;
bv_util bvutil(m);
bool internalized = false;
if (is_uninterp_const(v) && m.is_bool(v)) {
sat::bool_var b = m_map.to_bool_var(v);
if (b != sat::null_bool_var) {
bvars.push_back(b);
internalized = true;
}
}
else if (is_uninterp_const(v) && const2bits.find(to_app(v)->get_decl(), bv)) {
SASSERT(bvutil.is_bv(bv));
app* abv = to_app(bv);
internalized = true;
for (expr* arg : *abv) {
SASSERT(is_uninterp_const(arg));
sat::bool_var b = m_map.to_bool_var(arg);
if (b == sat::null_bool_var) {
internalized = false;
}
else {
bvars.push_back(b);
}
}
CTRACE("sat", internalized, tout << "var: " << bvars << "\n";);
}
else if (is_uninterp_const(v) && bvutil.is_bv(v)) {
// variable does not occur in assertions, so is unconstrained.
}
CTRACE("sat", !internalized, tout << "unhandled variable " << mk_pp(v, m) << "\n";);
return internalized;
}
bool extract_fixed_variable(u_map& asm2dep, expr* v, u_map const& bool_var2conseq, vector const& lconseq, expr_ref& conseq) {
sat::bool_var_vector bvars;
if (!internalize_var(v, bvars)) {
return false;
}
sat::literal_vector value;
sat::literal_set premises;
for (sat::bool_var bv : bvars) {
unsigned index;
if (bool_var2conseq.find(bv, index)) {
value.push_back(lconseq[index][0]);
for (unsigned j = 1; j < lconseq[index].size(); ++j) {
premises.insert(lconseq[index][j]);
}
}
else {
TRACE("sat", tout << "variable is not bound " << mk_pp(v, m) << "\n";);
return false;
}
}
expr_ref val(m);
expr_ref_vector conj(m);
internalize_value(value, v, val);
while (!premises.empty()) {
expr* e = nullptr;
VERIFY(asm2dep.find(premises.pop().index(), e));
conj.push_back(e);
}
conseq = m.mk_implies(mk_and(conj), val);
return true;
}
vector m_exps;
void internalize_value(sat::literal_vector const& value, expr* v, expr_ref& val) {
bv_util bvutil(m);
if (is_uninterp_const(v) && m.is_bool(v)) {
SASSERT(value.size() == 1);
val = value[0].sign() ? m.mk_not(v) : v;
}
else if (is_uninterp_const(v) && bvutil.is_bv_sort(v->get_sort())) {
SASSERT(value.size() == bvutil.get_bv_size(v));
if (m_exps.empty()) {
m_exps.push_back(rational::one());
}
while (m_exps.size() < value.size()) {
m_exps.push_back(rational(2)*m_exps.back());
}
rational r(0);
for (unsigned i = 0; i < value.size(); ++i) {
if (!value[i].sign()) {
r += m_exps[i];
}
}
val = m.mk_eq(v, bvutil.mk_numeral(r, value.size()));
}
else {
UNREACHABLE();
}
}
bool is_literal(expr* n) {
return is_uninterp_const(n) || (m.is_not(n, n) && is_uninterp_const(n));
}
bool is_clause(expr* fml) {
if (get_depth(fml) > 4)
return false;
if (is_literal(fml))
return true;
if (m.is_or(fml) || m.is_and(fml) || m.is_implies(fml) || m.is_not(fml) || m.is_iff(fml)) {
for (expr* n : *to_app(fml))
if (!is_clause(n))
return false;
return true;
}
return false;
}
lbool internalize_formulas() {
if (m_fmls_head == m_fmls.size())
return l_true;
lbool res;
if (m_is_cnf) {
res = internalize_goal(m_fmls.size() - m_fmls_head, m_fmls.data() + m_fmls_head);
}
else {
goal_ref g = alloc(goal, m, true, false); // models, maybe cores are enabled
for (unsigned i = m_fmls_head ; i < m_fmls.size(); ++i) {
expr* fml = m_fmls.get(i);
g->assert_expr(fml);
}
res = internalize_goal(g);
}
if (res != l_undef)
m_fmls_head = m_fmls.size();
m_internalized_converted = false;
return res;
}
void extract_assumptions(unsigned sz, expr* const* asms) {
m_asms.reset();
unsigned j = 0;
sat::literal lit;
sat::literal_set seen;
for (unsigned i = 0; i < sz; ++i) {
if (m_dep2asm.find(asms[i], lit)) {
SASSERT(lit.var() <= m_solver.num_vars());
if (!seen.contains(lit)) {
m_asms.push_back(lit);
seen.insert(lit);
if (i != j && !m_weights.empty()) {
m_weights[j] = m_weights[i];
}
++j;
}
}
}
for (unsigned i = 0; i < get_num_assumptions(); ++i) {
if (m_dep2asm.find(get_assumption(i), lit)) {
SASSERT(lit.var() <= m_solver.num_vars());
if (!seen.contains(lit)) {
m_asms.push_back(lit);
seen.insert(lit);
}
}
}
CTRACE("sat", m_dep2asm.size() != m_asms.size(),
tout << m_dep2asm.size() << " vs " << m_asms.size() << "\n";
tout << m_asms << "\n";
for (auto const& kv : m_dep2asm) {
tout << mk_pp(kv.m_key, m) << " " << kv.m_value << "\n";
});
SASSERT(m_dep2asm.size() == m_asms.size());
}
void extract_asm2dep(u_map& asm2dep) {
for (auto const& kv : m_dep2asm) {
asm2dep.insert(kv.m_value.index(), kv.m_key);
}
}
void extract_core(obj_map const& asm2fml) {
u_map asm2dep;
extract_asm2dep(asm2dep);
sat::literal_vector const& core = m_solver.get_core();
TRACE("sat",
for (auto const& kv : m_dep2asm) {
tout << mk_pp(kv.m_key, m) << " |-> " << sat::literal(kv.m_value) << "\n";
}
tout << "asm2fml: ";
for (auto const& kv : asm2fml) {
tout << mk_pp(kv.m_key, m) << " |-> " << mk_pp(kv.m_value, m) << "\n";
}
tout << "core: "; for (auto c : core) tout << c << " "; tout << "\n";
m_solver.display(tout);
);
m_core.reset();
for (sat::literal c : core) {
expr* e = nullptr;
VERIFY(asm2dep.find(c.index(), e));
if (asm2fml.contains(e)) {
e = asm2fml.find(e);
}
m_core.push_back(e);
}
}
void check_assumptions() {
sat::model const & ll_m = m_solver.get_model();
for (auto const& kv : m_dep2asm) {
sat::literal lit = kv.m_value;
if (sat::value_at(lit, ll_m) != l_true) {
IF_VERBOSE(0, verbose_stream() << mk_pp(kv.m_key, m) << " does not evaluate to true\n";
verbose_stream() << m_asms << "\n";
m_solver.display_assignment(verbose_stream());
m_solver.display(verbose_stream()););
throw default_exception("bad state");
}
}
}
void get_model_core(model_ref & mdl) override {
TRACE("sat", tout << "retrieve model " << (m_solver.model_is_current()?"present":"absent") << "\n";);
if (!m_solver.model_is_current()) {
mdl = nullptr;
return;
}
if (m_fmls.size() > m_fmls_head) {
mdl = nullptr;
return;
}
TRACE("sat", m_solver.display_model(tout););
CTRACE("sat", m_sat_mc, m_sat_mc->display(tout););
sat::model ll_m = m_solver.get_model();
mdl = alloc(model, m);
if (m_sat_mc) {
(*m_sat_mc)(ll_m);
}
expr_ref_vector var2expr(m);
m_map.mk_var_inv(var2expr);
for (unsigned v = 0; v < var2expr.size(); ++v) {
expr * n = var2expr.get(v);
if (!n || !is_uninterp_const(n)) {
continue;
}
switch (sat::value_at(v, ll_m)) {
case l_true:
mdl->register_decl(to_app(n)->get_decl(), m.mk_true());
break;
case l_false:
mdl->register_decl(to_app(n)->get_decl(), m.mk_false());
break;
default:
break;
}
}
TRACE("sat", m_solver.display(tout););
if (m_sat_mc) {
(*m_sat_mc)(mdl);
}
m_goal2sat.update_model(mdl);
if (m_mcs.back()) {
TRACE("sat", m_mcs.back()->display(tout););
(*m_mcs.back())(mdl);
}
TRACE("sat", model_smt2_pp(tout, m, *mdl, 0););
if (!gparams::get_ref().get_bool("model_validate", false)) {
return;
}
IF_VERBOSE(1, verbose_stream() << "Verifying solution\n";);
model_evaluator eval(*mdl);
eval.set_model_completion(true);
bool all_true = true;
for (expr * f : m_fmls) {
if (has_quantifiers(f))
continue;
expr_ref tmp(m);
eval(f, tmp);
if (m.limit().is_canceled())
return;
CTRACE("sat", !m.is_true(tmp),
tout << "Evaluation failed: " << mk_pp(f, m) << " to " << tmp << "\n";
model_smt2_pp(tout, m, *(mdl.get()), 0););
if (m.is_false(tmp)) {
IF_VERBOSE(0, verbose_stream() << "failed to verify: " << mk_pp(f, m) << "\n");
IF_VERBOSE(0, verbose_stream() << "evaluated to " << tmp << "\n");
all_true = false;
}
}
if (!all_true) {
IF_VERBOSE(0, verbose_stream() << m_params << "\n");
IF_VERBOSE(0, if (m_mcs.back()) m_mcs.back()->display(verbose_stream() << "mc0\n"));
IF_VERBOSE(0, for (auto const& kv : m_map) verbose_stream() << mk_pp(kv.m_key, m) << " |-> " << kv.m_value << "\n");
exit(0);
}
else {
IF_VERBOSE(1, verbose_stream() << "solution verified\n");
}
}
};
solver* mk_inc_sat_solver(ast_manager& m, params_ref const& p, bool incremental_mode) {
return alloc(inc_sat_solver, m, p, incremental_mode);
}
void inc_sat_display(std::ostream& out, solver& _s, unsigned sz, expr*const* soft, rational const* _weights) {
inc_sat_solver& s = dynamic_cast(_s);
vector weights;
for (unsigned i = 0; _weights && i < sz; ++i) {
if (!_weights[i].is_unsigned()) {
throw default_exception("Cannot display weights that are not integers");
}
weights.push_back(_weights[i].get_unsigned());
}
s.display_weighted(out, sz, soft, weights.data());
}
tactic * mk_psat_tactic(ast_manager& m, params_ref const& p) {
parallel_params pp(p);
return pp.enable() ? mk_parallel_tactic(mk_inc_sat_solver(m, p, false), p) : mk_sat_tactic(m);
}