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z3/src/muz/base/dl_context.cpp
2013-10-18 17:26:41 -07:00

1335 lines
44 KiB
C++

/*++
Copyright (c) 2006 Microsoft Corporation
Module Name:
dl_context.cpp
Abstract:
<abstract>
Author:
Leonardo de Moura (leonardo) 2010-05-18.
Revision History:
--*/
#include<sstream>
#include<limits>
#include"arith_decl_plugin.h"
#include"bv_decl_plugin.h"
#include"dl_context.h"
#include"for_each_expr.h"
#include"ast_smt_pp.h"
#include"ast_smt2_pp.h"
#include"datatype_decl_plugin.h"
#include"scoped_proof.h"
#include"fixedpoint_params.hpp"
namespace datalog {
// -----------------------------------
//
// context::sort_domain
//
// -----------------------------------
class context::sort_domain {
private:
sort_kind m_kind;
protected:
sort_ref m_sort;
bool m_limited_size;
uint64 m_size;
sort_domain(sort_kind k, context & ctx, sort * s)
: m_kind(k), m_sort(s, ctx.get_manager()) {
m_limited_size = ctx.get_decl_util().try_get_size(s, m_size);
}
public:
virtual ~sort_domain() {}
sort_kind get_kind() const { return m_kind; }
virtual unsigned get_constant_count() const = 0;
virtual void print_element(finite_element el_num, std::ostream & out) = 0;
};
class context::symbol_sort_domain : public sort_domain {
typedef map<symbol, finite_element, symbol_hash_proc, symbol_eq_proc> sym2num;
typedef svector<symbol> num2sym;
sym2num m_el_numbers;
num2sym m_el_names;
public:
symbol_sort_domain(context & ctx, sort * s) : sort_domain(SK_SYMBOL, ctx, s) {}
finite_element get_number(symbol sym) {
//we number symbols starting from zero, so table->size() is equal to the
//index of the symbol to be added next
unsigned newIdx = m_el_numbers.size();
sym2num::entry* sym_e = m_el_numbers.insert_if_not_there2(sym, newIdx);
unsigned idx=sym_e->get_data().m_value;
if (idx==newIdx) {
m_el_names.push_back(sym);
SASSERT(m_el_names.size()==m_el_numbers.size());
}
if (m_limited_size && idx>=m_size) {
std::stringstream sstm;
sstm << "sort " << m_sort->get_name() << " contains more constants than its declared size " << m_size;
throw default_exception(sstm.str());
}
return idx;
}
virtual unsigned get_constant_count() const {
return m_el_names.size();
}
virtual void print_element(finite_element el_num, std::ostream & out) {
if (el_num>=m_el_names.size()) {
out << el_num;
return;
}
out << m_el_names[el_num];
}
};
class context::uint64_sort_domain : public sort_domain {
typedef map<uint64, finite_element, uint64_hash, default_eq<uint64> > el2num;
typedef svector<uint64> num2el;
el2num m_el_numbers;
num2el m_el_names;
public:
uint64_sort_domain(context & ctx, sort * s) : sort_domain(SK_UINT64, ctx, s) {}
finite_element get_number(uint64 el) {
//we number symbols starting from zero, so table->size() is equal to the
//index of the symbol to be added next
unsigned newIdx = m_el_numbers.size();
el2num::entry* sym_e = m_el_numbers.insert_if_not_there2(el, newIdx);
unsigned idx=sym_e->get_data().m_value;
if (idx==newIdx) {
m_el_names.push_back(el);
SASSERT(m_el_names.size()==m_el_numbers.size());
}
if (m_limited_size && idx>=m_size) {
std::stringstream sstm;
sstm << "sort " << m_sort->get_name() << " contains more constants than its declared size " << m_size;
throw default_exception(sstm.str());
}
return idx;
}
virtual unsigned get_constant_count() const {
return m_el_names.size();
}
virtual void print_element(finite_element el_num, std::ostream & out) {
if (el_num >= m_el_names.size()) {
out << "<unk " << m_sort->get_name() << ":" << el_num << '>';
return;
}
out << m_el_names[el_num];
}
};
// -----------------------------------
//
// trail stack for restoring rules
//
// -----------------------------------
class context::restore_rules : public trail<context> {
rule_set* m_old_rules;
void reset() {
dealloc(m_old_rules);
m_old_rules = 0;
}
public:
restore_rules(rule_set& r): m_old_rules(alloc(rule_set, r)) {}
virtual ~restore_rules() {}
virtual void undo(context& ctx) {
ctx.replace_rules(*m_old_rules);
reset();
}
};
template<typename Ctx, typename Vec>
class restore_vec_size_trail : public trail<Ctx> {
Vec& m_vector;
unsigned m_old_size;
public:
restore_vec_size_trail(Vec& v): m_vector(v), m_old_size(v.size()) {}
virtual ~restore_vec_size_trail() {}
virtual void undo(Ctx& ctx) { m_vector.shrink(m_old_size); }
};
void context::push() {
m_trail.push_scope();
m_trail.push(restore_rules(m_rule_set));
m_trail.push(restore_vec_size_trail<context,expr_ref_vector>(m_rule_fmls));
m_trail.push(restore_vec_size_trail<context,expr_ref_vector>(m_background));
}
void context::pop() {
if (m_trail.get_num_scopes() == 0) {
throw default_exception("there are no backtracking points to pop to");
}
m_trail.pop_scope(1);
}
// -----------------------------------
//
// context
//
// -----------------------------------
context::context(ast_manager & m, register_engine_base& re, smt_params& fp, params_ref const& pa):
m(m),
m_register_engine(re),
m_fparams(fp),
m_params_ref(pa),
m_params(alloc(fixedpoint_params, m_params_ref)),
m_decl_util(m),
m_rewriter(m),
m_var_subst(m),
m_rule_manager(*this),
m_elim_unused_vars(m),
m_abstractor(m),
m_contains_p(*this),
m_check_pred(m_contains_p, m),
m_transf(*this),
m_trail(*this),
m_pinned(m),
m_vars(m),
m_rule_set(*this),
m_transformed_rule_set(*this),
m_rule_fmls_head(0),
m_rule_fmls(m),
m_background(m),
m_mc(0),
m_rel(0),
m_engine(0),
m_closed(false),
m_saturation_was_run(false),
m_last_status(OK),
m_last_answer(m),
m_engine_type(LAST_ENGINE),
m_cancel(false) {
re.set_context(this);
}
context::~context() {
reset();
dealloc(m_params);
}
void context::reset() {
m_trail.reset();
m_rule_set.reset();
m_rule_fmls_head = 0;
m_rule_fmls.reset();
m_rule_names.reset();
m_argument_var_names.reset();
m_preds.reset();
m_preds_by_name.reset();
reset_dealloc_values(m_sorts);
m_engine = 0;
m_rel = 0;
}
bool context::is_fact(app * head) const {
return m_rule_manager.is_fact(head);
}
bool context::has_sort_domain(relation_sort s) const {
return m_sorts.contains(s);
}
context::sort_domain & context::get_sort_domain(relation_sort s) {
return *m_sorts.find(s);
}
const context::sort_domain & context::get_sort_domain(relation_sort s) const {
return *m_sorts.find(s);
}
bool context::generate_proof_trace() const { return m_params->generate_proof_trace(); }
bool context::output_profile() const { return m_params->output_profile(); }
bool context::output_tuples() const { return m_params->output_tuples(); }
bool context::use_map_names() const { return m_params->use_map_names(); }
bool context::fix_unbound_vars() const { return m_params->fix_unbound_vars(); }
symbol context::default_table() const { return m_params->default_table(); }
symbol context::default_relation() const { return m_params->default_relation(); } // external_relation_plugin::get_name());
symbol context::default_table_checker() const { return m_params->default_table_checker(); }
bool context::default_table_checked() const { return m_params->default_table_checked(); }
bool context::dbg_fpr_nonempty_relation_signature() const { return m_params->dbg_fpr_nonempty_relation_signature(); }
unsigned context::dl_profile_milliseconds_threshold() const { return m_params->profile_timeout_milliseconds(); }
bool context::all_or_nothing_deltas() const { return m_params->all_or_nothing_deltas(); }
bool context::compile_with_widening() const { return m_params->compile_with_widening(); }
bool context::unbound_compressor() const { return m_params->unbound_compressor(); }
bool context::similarity_compressor() const { return m_params->similarity_compressor(); }
unsigned context::similarity_compressor_threshold() const { return m_params->similarity_compressor_threshold(); }
unsigned context::soft_timeout() const { return m_fparams.m_soft_timeout; }
unsigned context::initial_restart_timeout() const { return m_params->initial_restart_timeout(); }
bool context::generate_explanations() const { return m_params->generate_explanations(); }
bool context::explanations_on_relation_level() const { return m_params->explanations_on_relation_level(); }
bool context::magic_sets_for_queries() const { return m_params->magic_sets_for_queries(); }
bool context::eager_emptiness_checking() const { return m_params->eager_emptiness_checking(); }
bool context::bit_blast() const { return m_params->bit_blast(); }
bool context::karr() const { return m_params->karr(); }
bool context::scale() const { return m_params->scale(); }
bool context::magic() const { return m_params->magic(); }
bool context::quantify_arrays() const { return m_params->quantify_arrays(); }
bool context::instantiate_quantifiers() const { return m_params->instantiate_quantifiers(); }
void context::register_finite_sort(sort * s, sort_kind k) {
m_pinned.push_back(s);
SASSERT(!m_sorts.contains(s));
sort_domain * dom;
switch (k) {
case SK_SYMBOL:
dom = alloc(symbol_sort_domain, *this, s);
break;
case SK_UINT64:
dom = alloc(uint64_sort_domain, *this, s);
break;
default:
UNREACHABLE();
}
m_sorts.insert(s, dom);
}
void context::register_variable(func_decl* var) {
m_vars.push_back(m.mk_const(var));
}
expr_ref context::bind_variables(expr* fml, bool is_forall) {
expr_ref result(m);
app_ref_vector const & vars = m_vars;
rule_manager& rm = get_rule_manager();
if (vars.empty()) {
result = fml;
}
else {
m_names.reset();
m_abstractor(0, vars.size(), reinterpret_cast<expr*const*>(vars.c_ptr()), fml, result);
rm.collect_vars(result);
ptr_vector<sort>& sorts = rm.get_var_sorts();
if (sorts.empty()) {
result = fml;
}
else {
for (unsigned i = 0; i < sorts.size(); ++i) {
if (!sorts[i]) {
if (i < vars.size()) {
sorts[i] = vars[i]->get_decl()->get_range();
}
else {
sorts[i] = m.mk_bool_sort();
}
}
if (i < vars.size()) {
m_names.push_back(vars[i]->get_decl()->get_name());
}
else {
m_names.push_back(symbol(i));
}
}
quantifier_ref q(m);
sorts.reverse();
q = m.mk_quantifier(is_forall, sorts.size(), sorts.c_ptr(), m_names.c_ptr(), result);
m_elim_unused_vars(q, result);
}
}
return result;
}
void context::register_predicate(func_decl * decl, bool named) {
if (!is_predicate(decl)) {
m_pinned.push_back(decl);
m_preds.insert(decl);
if (named) {
m_preds_by_name.insert(decl->get_name(), decl);
}
}
}
void context::restrict_predicates(func_decl_set const& preds) {
m_preds.reset();
func_decl_set::iterator it = preds.begin(), end = preds.end();
for (; it != end; ++it) {
m_preds.insert(*it);
}
}
context::finite_element context::get_constant_number(relation_sort srt, symbol sym) {
sort_domain & dom0 = get_sort_domain(srt);
SASSERT(dom0.get_kind() == SK_SYMBOL);
symbol_sort_domain & dom = static_cast<symbol_sort_domain &>(dom0);
return dom.get_number(sym);
}
context::finite_element context::get_constant_number(relation_sort srt, uint64 el) {
sort_domain & dom0 = get_sort_domain(srt);
SASSERT(dom0.get_kind()==SK_UINT64);
uint64_sort_domain & dom = static_cast<uint64_sort_domain &>(dom0);
return dom.get_number(el);
}
void context::print_constant_name(relation_sort srt, uint64 num, std::ostream & out)
{
if (has_sort_domain(srt)) {
SASSERT(num<=UINT_MAX);
get_sort_domain(srt).print_element(static_cast<unsigned>(num), out);
}
else {
out << num;
}
}
bool context::try_get_sort_constant_count(relation_sort srt, uint64 & constant_count) {
if (!has_sort_domain(srt)) {
return false;
}
constant_count = get_sort_domain(srt).get_constant_count();
return true;
}
uint64 context::get_sort_size_estimate(relation_sort srt) {
if (get_decl_util().is_rule_sort(srt)) {
return 1;
}
uint64 res;
if (!try_get_sort_constant_count(srt, res)) {
sort_size sz = srt->get_num_elements();
if (sz.is_finite()) {
res = sz.size();
}
else {
res = std::numeric_limits<uint64>::max();
}
}
return res;
}
void context::set_argument_names(const func_decl * pred, svector<symbol> var_names)
{
SASSERT(!m_argument_var_names.contains(pred));
m_argument_var_names.insert(pred, var_names);
}
symbol context::get_argument_name(const func_decl * pred, unsigned arg_index)
{
pred2syms::obj_map_entry * e = m_argument_var_names.find_core(pred);
if (!e) {
std::stringstream name_stm;
name_stm << '#' << arg_index;
return symbol(name_stm.str().c_str());
}
SASSERT(arg_index < e->get_data().m_value.size());
return e->get_data().m_value[arg_index];
}
void context::set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
symbol const * relation_names) {
if (relation_name_cnt > 0) {
ensure_engine();
}
if (relation_name_cnt > 0 && m_rel) {
m_rel->set_predicate_representation(pred, relation_name_cnt, relation_names);
}
}
func_decl * context::mk_fresh_head_predicate(symbol const & prefix, symbol const & suffix,
unsigned arity, sort * const * domain, func_decl* orig_pred) {
func_decl* new_pred =
m.mk_fresh_func_decl(prefix, suffix, arity, domain, m.mk_bool_sort());
register_predicate(new_pred, true);
if (m_rel) {
m_rel->inherit_predicate_kind(new_pred, orig_pred);
}
return new_pred;
}
void context::add_rule(expr* rl, symbol const& name) {
m_rule_fmls.push_back(rl);
m_rule_names.push_back(name);
}
void context::flush_add_rules() {
datalog::rule_manager& rm = get_rule_manager();
scoped_proof_mode _scp(m, generate_proof_trace()?PGM_FINE:PGM_DISABLED);
while (m_rule_fmls_head < m_rule_fmls.size()) {
expr* fml = m_rule_fmls[m_rule_fmls_head].get();
proof* p = generate_proof_trace()?m.mk_asserted(fml):0;
rm.mk_rule(fml, p, m_rule_set, m_rule_names[m_rule_fmls_head]);
++m_rule_fmls_head;
}
rule_set::iterator it = m_rule_set.begin(), end = m_rule_set.end();
rule_ref r(m_rule_manager);
for (; it != end; ++it) {
r = *it;
check_rule(r);
}
}
//
// Update a rule with a new.
// It requires basic subsumption.
//
void context::update_rule(expr* rl, symbol const& name) {
datalog::rule_manager& rm = get_rule_manager();
proof* p = 0;
if (generate_proof_trace()) {
p = m.mk_asserted(rl);
}
unsigned size_before = m_rule_set.get_num_rules();
rm.mk_rule(rl, p, m_rule_set, name);
unsigned size_after = m_rule_set.get_num_rules();
if (size_before + 1 != size_after) {
std::stringstream strm;
strm << "Rule " << name << " has a non-trivial body. It cannot be modified";
throw default_exception(strm.str());
}
// The new rule is inserted last:
rule_ref r(m_rule_set.get_rule(size_before), rm);
rule_ref_vector const& rls = m_rule_set.get_rules();
rule* old_rule = 0;
for (unsigned i = 0; i < size_before; ++i) {
if (rls[i]->name() == name) {
if (old_rule) {
std::stringstream strm;
strm << "Rule " << name << " occurs twice. It cannot be modified";
m_rule_set.del_rule(r);
throw default_exception(strm.str());
}
old_rule = rls[i];
}
}
if (old_rule) {
if (!check_subsumes(*old_rule, *r)) {
std::stringstream strm;
strm << "Old rule ";
old_rule->display(*this, strm);
strm << "does not subsume new rule ";
r->display(*this, strm);
m_rule_set.del_rule(r);
throw default_exception(strm.str());
}
m_rule_set.del_rule(old_rule);
}
}
bool context::check_subsumes(rule const& stronger_rule, rule const& weaker_rule) {
if (stronger_rule.get_head() != weaker_rule.get_head()) {
return false;
}
for (unsigned i = 0; i < stronger_rule.get_tail_size(); ++i) {
app* t = stronger_rule.get_tail(i);
bool found = false;
for (unsigned j = 0; j < weaker_rule.get_tail_size(); ++j) {
app* s = weaker_rule.get_tail(j);
if (s == t) {
found = true;
break;
}
}
if (!found) {
return false;
}
}
return true;
}
unsigned context::get_num_levels(func_decl* pred) {
ensure_engine();
return m_engine->get_num_levels(pred);
}
expr_ref context::get_cover_delta(int level, func_decl* pred) {
ensure_engine();
return m_engine->get_cover_delta(level, pred);
}
void context::add_cover(int level, func_decl* pred, expr* property) {
ensure_engine();
m_engine->add_cover(level, pred, property);
}
void context::check_uninterpreted_free(rule_ref& r) {
func_decl* f = 0;
if (r->has_uninterpreted_non_predicates(f)) {
std::stringstream stm;
stm << "Uninterpreted '"
<< f->get_name()
<< "' in ";
r->display(*this, stm);
throw default_exception(stm.str());
}
}
void context::check_quantifier_free(rule_ref& r) {
if (r->has_quantifiers()) {
std::stringstream stm;
stm << "cannot process quantifiers in rule ";
r->display(*this, stm);
throw default_exception(stm.str());
}
}
void context::check_existential_tail(rule_ref& r) {
unsigned ut_size = r->get_uninterpreted_tail_size();
unsigned t_size = r->get_tail_size();
TRACE("dl", r->display_smt2(get_manager(), tout); tout << "\n";);
for (unsigned i = ut_size; i < t_size; ++i) {
app* t = r->get_tail(i);
TRACE("dl", tout << "checking: " << mk_ismt2_pp(t, get_manager()) << "\n";);
if (m_check_pred(t)) {
std::ostringstream out;
out << "interpreted body " << mk_ismt2_pp(t, get_manager()) << " contains recursive predicate";
throw default_exception(out.str());
}
}
}
void context::check_positive_predicates(rule_ref& r) {
ast_mark visited;
ptr_vector<expr> todo, tocheck;
unsigned ut_size = r->get_uninterpreted_tail_size();
unsigned t_size = r->get_tail_size();
for (unsigned i = 0; i < ut_size; ++i) {
if (r->is_neg_tail(i)) {
tocheck.push_back(r->get_tail(i));
}
}
ast_manager& m = get_manager();
contains_pred contains_p(*this);
check_pred check_pred(contains_p, get_manager());
for (unsigned i = ut_size; i < t_size; ++i) {
todo.push_back(r->get_tail(i));
}
while (!todo.empty()) {
expr* e = todo.back(), *e1, *e2;
todo.pop_back();
if (visited.is_marked(e)) {
continue;
}
visited.mark(e, true);
if (is_predicate(e)) {
}
else if (m.is_and(e) || m.is_or(e)) {
todo.append(to_app(e)->get_num_args(), to_app(e)->get_args());
}
else if (m.is_implies(e, e1, e2)) {
tocheck.push_back(e1);
todo.push_back(e2);
}
else if (is_quantifier(e)) {
todo.push_back(to_quantifier(e)->get_expr());
}
else if ((m.is_eq(e, e1, e2) || m.is_iff(e, e1, e2)) &&
m.is_true(e1)) {
todo.push_back(e2);
}
else if ((m.is_eq(e, e1, e2) || m.is_iff(e, e1, e2)) &&
m.is_true(e2)) {
todo.push_back(e1);
}
else {
tocheck.push_back(e);
}
}
for (unsigned i = 0; i < tocheck.size(); ++i) {
expr* e = tocheck[i];
if (check_pred(e)) {
std::ostringstream out;
out << "recursive predicate " << mk_ismt2_pp(e, get_manager()) << " occurs nested in body";
r->display(*this, out << "\n");
throw default_exception(out.str());
}
}
}
void context::check_rule(rule_ref& r) {
switch(get_engine()) {
case DATALOG_ENGINE:
check_quantifier_free(r);
check_uninterpreted_free(r);
check_existential_tail(r);
break;
case PDR_ENGINE:
check_existential_tail(r);
check_positive_predicates(r);
check_uninterpreted_free(r);
break;
case QPDR_ENGINE:
check_positive_predicates(r);
check_uninterpreted_free(r);
break;
case BMC_ENGINE:
check_positive_predicates(r);
break;
case QBMC_ENGINE:
check_existential_tail(r);
check_positive_predicates(r);
break;
case TAB_ENGINE:
check_existential_tail(r);
check_positive_predicates(r);
break;
case DUALITY_ENGINE:
check_existential_tail(r);
check_positive_predicates(r);
break;
case CLP_ENGINE:
check_existential_tail(r);
check_positive_predicates(r);
break;
case LAST_ENGINE:
default:
UNREACHABLE();
break;
}
if (generate_proof_trace() && !r->get_proof()) {
m_rule_manager.mk_rule_asserted_proof(*r.get());
}
}
void context::add_rule(rule_ref& r) {
m_rule_set.add_rule(r);
}
void context::add_fact(func_decl * pred, const relation_fact & fact) {
if (get_engine() == DATALOG_ENGINE) {
ensure_engine();
m_rel->add_fact(pred, fact);
}
else {
expr_ref rule(m.mk_app(pred, fact.size(), (expr*const*)fact.c_ptr()), m);
add_rule(rule, symbol::null);
}
}
void context::add_fact(app * head) {
SASSERT(is_fact(head));
relation_fact fact(get_manager());
unsigned n = head->get_num_args();
for (unsigned i = 0; i < n; i++) {
fact.push_back(to_app(head->get_arg(i)));
}
add_fact(head->get_decl(), fact);
}
bool context::has_facts(func_decl * pred) const {
return m_rel && m_rel->has_facts(pred);
}
void context::add_table_fact(func_decl * pred, const table_fact & fact) {
if (get_engine() == DATALOG_ENGINE) {
ensure_engine();
m_rel->add_fact(pred, fact);
}
else {
relation_fact rfact(m);
for (unsigned i = 0; i < fact.size(); ++i) {
rfact.push_back(m_decl_util.mk_numeral(fact[i], pred->get_domain()[i]));
}
add_fact(pred, rfact);
}
}
void context::add_table_fact(func_decl * pred, unsigned num_args, unsigned args[]) {
if (pred->get_arity() != num_args) {
std::ostringstream out;
out << "miss-matched number of arguments passed to " << mk_ismt2_pp(pred, m) << " " << num_args << " passed";
throw default_exception(out.str());
}
table_fact fact;
for (unsigned i = 0; i < num_args; ++i) {
fact.push_back(args[i]);
}
add_table_fact(pred, fact);
}
void context::close() {
SASSERT(!m_closed);
if (!m_rule_set.close()) {
throw default_exception("Negation is not stratified!");
}
m_closed = true;
}
void context::ensure_closed() {
if (!m_closed) {
close();
}
}
void context::ensure_opened() {
if (m_closed) {
reopen();
}
}
void context::reopen() {
SASSERT(m_closed);
m_rule_set.reopen();
m_closed = false;
}
void context::transform_rules(rule_transformer::plugin* plugin) {
rule_transformer transformer(*this);
transformer.register_plugin(plugin);
transform_rules(transformer);
}
void context::transform_rules(rule_transformer& transf) {
SASSERT(m_closed); //we must finish adding rules before we start transforming them
TRACE("dl", display_rules(tout););
if (transf(m_rule_set)) {
//we have already ensured the negation is stratified and transformations
//should not break the stratification
m_rule_set.ensure_closed();
TRACE("dl", display_rules(tout););
TRACE("dl_verbose", display(tout););
}
}
void context::replace_rules(rule_set const & rs) {
SASSERT(!m_closed);
m_rule_set.replace_rules(rs);
if (m_rel) {
m_rel->restrict_predicates(get_predicates());
}
}
void context::record_transformed_rules() {
m_transformed_rule_set.replace_rules(m_rule_set);
}
void context::apply_default_transformation() {
}
void context::collect_params(param_descrs& p) {
fixedpoint_params::collect_param_descrs(p);
insert_timeout(p);
}
void context::updt_params(params_ref const& p) {
m_params_ref.copy(p);
if (m_engine.get()) m_engine->updt_params();
}
expr_ref context::get_background_assertion() {
expr_ref result(m);
switch (m_background.size()) {
case 0: result = m.mk_true(); break;
case 1: result = m_background[0].get(); break;
default: result = m.mk_and(m_background.size(), m_background.c_ptr()); break;
}
return result;
}
void context::assert_expr(expr* e) {
TRACE("dl", tout << mk_ismt2_pp(e, m) << "\n";);
m_background.push_back(e);
}
void context::cancel() {
m_cancel = true;
m_last_status = CANCELED;
m_transf.cancel();
if (m_engine) m_engine->cancel();
}
void context::cleanup() {
m_cancel = false;
m_last_status = OK;
if (m_engine) m_engine->cleanup();
}
class context::engine_type_proc {
ast_manager& m;
arith_util a;
datatype_util dt;
DL_ENGINE m_engine_type;
public:
engine_type_proc(ast_manager& m): m(m), a(m), dt(m), m_engine_type(DATALOG_ENGINE) {}
DL_ENGINE get_engine() const { return m_engine_type; }
void operator()(expr* e) {
if (is_quantifier(e)) {
m_engine_type = QPDR_ENGINE;
}
else if (m_engine_type != QPDR_ENGINE) {
if (a.is_int_real(e)) {
m_engine_type = PDR_ENGINE;
}
else if (is_var(e) && m.is_bool(e)) {
m_engine_type = PDR_ENGINE;
}
else if (dt.is_datatype(m.get_sort(e))) {
m_engine_type = PDR_ENGINE;
}
}
}
};
void context::configure_engine() {
symbol e = m_params->engine();
if (e == symbol("datalog")) {
m_engine_type = DATALOG_ENGINE;
}
else if (e == symbol("pdr")) {
m_engine_type = PDR_ENGINE;
}
else if (e == symbol("qpdr")) {
m_engine_type = QPDR_ENGINE;
}
else if (e == symbol("bmc")) {
m_engine_type = BMC_ENGINE;
}
else if (e == symbol("qbmc")) {
m_engine_type = QBMC_ENGINE;
}
else if (e == symbol("tab")) {
m_engine_type = TAB_ENGINE;
}
else if (e == symbol("clp")) {
m_engine_type = CLP_ENGINE;
}
else if (e == symbol("duality")) {
m_engine_type = DUALITY_ENGINE;
}
if (m_engine_type == LAST_ENGINE) {
expr_fast_mark1 mark;
engine_type_proc proc(m);
m_engine_type = DATALOG_ENGINE;
for (unsigned i = 0; m_engine_type == DATALOG_ENGINE && i < m_rule_set.get_num_rules(); ++i) {
rule * r = m_rule_set.get_rule(i);
quick_for_each_expr(proc, mark, r->get_head());
for (unsigned j = 0; j < r->get_tail_size(); ++j) {
quick_for_each_expr(proc, mark, r->get_tail(j));
}
m_engine_type = proc.get_engine();
}
for (unsigned i = m_rule_fmls_head; m_engine_type == DATALOG_ENGINE && i < m_rule_fmls.size(); ++i) {
expr* fml = m_rule_fmls[i].get();
while (is_quantifier(fml)) {
fml = to_quantifier(fml)->get_expr();
}
quick_for_each_expr(proc, mark, fml);
m_engine_type = proc.get_engine();
}
}
}
lbool context::query(expr* query) {
#if 0
// TODO: what?
if(get_engine() != DUALITY_ENGINE) {
new_query();
rule_set::iterator it = m_rule_set.begin(), end = m_rule_set.end();
rule_ref r(m_rule_manager);
for (; it != end; ++it) {
r = *it;
check_rule(r);
}
}
#endif
m_mc = mk_skip_model_converter();
m_last_status = OK;
m_last_answer = 0;
switch (get_engine()) {
case DATALOG_ENGINE:
case PDR_ENGINE:
case QPDR_ENGINE:
case BMC_ENGINE:
case QBMC_ENGINE:
case TAB_ENGINE:
case CLP_ENGINE:
flush_add_rules();
break;
case DUALITY_ENGINE:
break;
default:
UNREACHABLE();
}
ensure_engine();
return m_engine->query(query);
}
model_ref context::get_model() {
ensure_engine();
return m_engine->get_model();
}
proof_ref context::get_proof() {
ensure_engine();
return m_engine->get_proof();
}
void context::ensure_engine() {
if (!m_engine.get()) {
m_engine = m_register_engine.mk_engine(get_engine());
// break abstraction.
if (get_engine() == DATALOG_ENGINE) {
m_rel = dynamic_cast<rel_context_base*>(m_engine.get());
}
}
}
lbool context::rel_query(unsigned num_rels, func_decl * const* rels) {
ensure_engine();
return m_engine->query(num_rels, rels);
}
expr* context::get_answer_as_formula() {
if (m_last_answer) {
return m_last_answer.get();
}
ensure_engine();
m_last_answer = m_engine->get_answer();
return m_last_answer.get();
}
void context::display_certificate(std::ostream& out) {
ensure_engine();
m_engine->display_certificate(out);
}
void context::display(std::ostream & out) const {
display_rules(out);
if (m_rel) m_rel->display_facts(out);
}
void context::display_profile(std::ostream& out) const {
out << "\n---------------\n";
out << "Original rules\n";
display_rules(out);
out << "\n---------------\n";
out << "Transformed rules\n";
m_transformed_rule_set.display(out);
if (m_rel) {
m_rel->display_profile(out);
}
}
void context::reset_statistics() {
if (m_engine) {
m_engine->reset_statistics();
}
}
void context::collect_statistics(statistics& st) const {
if (m_engine) {
m_engine->collect_statistics(st);
}
}
execution_result context::get_status() { return m_last_status; }
bool context::result_contains_fact(relation_fact const& f) {
return m_rel && m_rel->result_contains_fact(f);
}
// NB: algebraic data-types declarations will not be printed.
class free_func_visitor {
ast_manager& m;
func_decl_set m_funcs;
obj_hashtable<sort> m_sorts;
public:
free_func_visitor(ast_manager& m): m(m) {}
void operator()(var * n) { }
void operator()(app * n) {
m_funcs.insert(n->get_decl());
sort* s = m.get_sort(n);
if (s->get_family_id() == null_family_id) {
m_sorts.insert(s);
}
}
void operator()(quantifier * n) { }
func_decl_set& funcs() { return m_funcs; }
obj_hashtable<sort>& sorts() { return m_sorts; }
};
static void collect_free_funcs(unsigned sz, expr* const* exprs,
expr_mark& visited, free_func_visitor& v,
mk_fresh_name& fresh_names) {
for (unsigned i = 0; i < sz; ++i) {
expr* e = exprs[i];
for_each_expr(v, visited, e);
while (is_quantifier(e)) {
e = to_quantifier(e)->get_expr();
}
fresh_names.add(e);
}
}
void context::get_raw_rule_formulas(expr_ref_vector& rules, svector<symbol>& names){
for (unsigned i = 0; i < m_rule_fmls.size(); ++i) {
expr_ref r = bind_variables(m_rule_fmls[i].get(), true);
rules.push_back(r.get());
// rules.push_back(m_rule_fmls[i].get());
names.push_back(m_rule_names[i]);
}
}
void context::get_rules_as_formulas(expr_ref_vector& rules, svector<symbol>& names) {
expr_ref fml(m);
datalog::rule_manager& rm = get_rule_manager();
// ensure that rules are all using bound variables.
for (unsigned i = m_rule_fmls_head; i < m_rule_fmls.size(); ++i) {
ptr_vector<sort> sorts;
get_free_vars(m_rule_fmls[i].get(), sorts);
if (!sorts.empty()) {
rm.mk_rule(m_rule_fmls[i].get(), 0, m_rule_set, m_rule_names[i]);
m_rule_fmls[i] = m_rule_fmls.back();
m_rule_names[i] = m_rule_names.back();
m_rule_fmls.pop_back();
m_rule_names.pop_back();
--i;
}
}
rule_set::iterator it = m_rule_set.begin(), end = m_rule_set.end();
for (; it != end; ++it) {
(*it)->to_formula(fml);
rules.push_back(fml);
names.push_back((*it)->name());
}
for (unsigned i = m_rule_fmls_head; i < m_rule_fmls.size(); ++i) {
rules.push_back(m_rule_fmls[i].get());
names.push_back(m_rule_names[i]);
}
}
void context::display_smt2(
unsigned num_queries,
expr* const* queries,
std::ostream& out) {
ast_manager& m = get_manager();
free_func_visitor visitor(m);
expr_mark visited;
func_decl_set rels;
unsigned num_axioms = m_background.size();
expr* const* axioms = m_background.c_ptr();
expr_ref fml(m);
expr_ref_vector rules(m);
svector<symbol> names;
bool use_fixedpoint_extensions = m_params->print_with_fixedpoint_extensions();
bool print_low_level = m_params->print_low_level_smt2();
bool do_declare_vars = m_params->print_with_variable_declarations();
#define PP(_e_) if (print_low_level) out << mk_smt_pp(_e_, m); else ast_smt2_pp(out, _e_, env);
get_rules_as_formulas(rules, names);
smt2_pp_environment_dbg env(m);
mk_fresh_name fresh_names;
collect_free_funcs(num_axioms, axioms, visited, visitor, fresh_names);
collect_free_funcs(rules.size(), rules.c_ptr(), visited, visitor, fresh_names);
collect_free_funcs(num_queries, queries, visited, visitor, fresh_names);
func_decl_set funcs;
func_decl_set::iterator it = visitor.funcs().begin();
func_decl_set::iterator end = visitor.funcs().end();
for (; it != end; ++it) {
func_decl* f = *it;
if (f->get_family_id() != null_family_id) {
//
}
else if (is_predicate(f) && use_fixedpoint_extensions) {
rels.insert(f);
}
else {
funcs.insert(f);
}
}
if (!use_fixedpoint_extensions) {
out << "(set-logic HORN)\n";
}
it = funcs.begin(), end = funcs.end();
obj_hashtable<sort>& sorts = visitor.sorts();
obj_hashtable<sort>::iterator sit = sorts.begin(), send = sorts.end();
for (; sit != send; ++sit) {
PP(*sit);
}
for (; it != end; ++it) {
func_decl* f = *it;
PP(f);
out << "\n";
}
it = rels.begin(); end = rels.end();
for (; it != end; ++it) {
func_decl* f = *it;
out << "(declare-rel " << f->get_name() << " (";
for (unsigned i = 0; i < f->get_arity(); ++i) {
ast_smt2_pp(out, f->get_domain(i), env);
if (i + 1 < f->get_arity()) {
out << " ";
}
}
out << "))\n";
}
if (use_fixedpoint_extensions && do_declare_vars) {
declare_vars(rules, fresh_names, out);
}
if (num_axioms > 0 && !use_fixedpoint_extensions) {
throw default_exception("Background axioms cannot be used with SMT-LIB2 HORN format");
}
for (unsigned i = 0; i < num_axioms; ++i) {
out << "(assert ";
PP(axioms[i]);
out << ")\n";
}
for (unsigned i = 0; i < rules.size(); ++i) {
out << (use_fixedpoint_extensions?"(rule ":"(assert ");
expr* r = rules[i].get();
symbol nm = names[i];
if (symbol::null != nm) {
out << "(! ";
}
PP(r);
if (symbol::null != nm) {
out << " :named ";
while (fresh_names.contains(nm)) {
std::ostringstream s;
s << nm << "!";
nm = symbol(s.str().c_str());
}
fresh_names.add(nm);
if (is_smt2_quoted_symbol(nm)) {
out << mk_smt2_quoted_symbol(nm);
}
else {
out << nm;
}
out << ")";
}
out << ")\n";
}
if (use_fixedpoint_extensions) {
for (unsigned i = 0; i < num_queries; ++i) {
out << "(query ";
PP(queries[i]);
out << ")\n";
}
}
else {
for (unsigned i = 0; i < num_queries; ++i) {
if (num_queries > 1) out << "(push)\n";
out << "(assert ";
expr_ref q(m);
q = m.mk_not(queries[i]);
PP(q);
out << ")\n";
out << "(check-sat)\n";
if (num_queries > 1) out << "(pop)\n";
}
}
}
void context::declare_vars(expr_ref_vector& rules, mk_fresh_name& fresh_names, std::ostream& out) {
//
// replace bound variables in rules by 'var declarations'
// First remove quantifers, then replace bound variables
// by fresh constants.
//
smt2_pp_environment_dbg env(m);
var_subst vsubst(m, false);
expr_ref_vector fresh_vars(m), subst(m);
expr_ref res(m);
obj_map<sort, unsigned_vector> var_idxs;
obj_map<sort, unsigned> max_vars;
for (unsigned i = 0; i < rules.size(); ++i) {
expr* r = rules[i].get();
if (!is_quantifier(r)) {
continue;
}
quantifier* q = to_quantifier(r);
if (!q->is_forall()) {
continue;
}
if (has_quantifiers(q->get_expr())) {
continue;
}
max_vars.reset();
subst.reset();
unsigned max_var = 0;
unsigned num_vars = q->get_num_decls();
for (unsigned j = 0; j < num_vars; ++j) {
sort* s = q->get_decl_sort(num_vars-1-j);
// maximal var for the given sort.
if (!max_vars.find(s, max_var)) {
max_var = 0;
}
else {
++max_var;
}
max_vars.insert(s, max_var);
// index into fresh variable array.
// unsigned fresh_var_idx = 0;
obj_map<sort, unsigned_vector>::obj_map_entry* e = var_idxs.insert_if_not_there2(s, unsigned_vector());
unsigned_vector& vars = e->get_data().m_value;
if (max_var >= vars.size()) {
SASSERT(vars.size() == max_var);
vars.push_back(fresh_vars.size());
symbol name = fresh_names.next();
fresh_vars.push_back(m.mk_const(name, s));
out << "(declare-var " << name << " ";
ast_smt2_pp(out, s, env);
out << ")\n";
}
subst.push_back(fresh_vars[vars[max_var]].get());
}
vsubst(q->get_expr(), subst.size(), subst.c_ptr(), res);
rules[i] = res.get();
}
}
};