mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-10-10 09:48:05 +00:00
Code Activity

Merge branch 'master' of https://github.com/z3prover/z3

Browse source
This commit is contained in:
Nikolaj Bjorner 2018-06-15 14:58:10 -07:00
commit 6fc08e9c9f
236 changed files with 14093 additions and 16593 deletions
Download patch file Download diff file Expand all files Collapse all files

2
src/muz/base/CMakeLists.txt
View file

@ -18,5 +18,5 @@ z3_add_component(muz
smt
smt2parser
PYG_FILES
fixedpoint_params.pyg
fp_params.pyg
)

134
src/muz/base/dl_context.cpp
View file

@ -27,7 +27,7 @@ Revision History:
#include "ast/ast_smt2_pp.h"
#include "ast/datatype_decl_plugin.h"
#include "ast/scoped_proof.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include "ast/ast_pp_util.h"
@ -152,15 +152,15 @@ namespace datalog {
class context::restore_rules : public trail<context> {
rule_set* m_old_rules;
void reset() {
dealloc(m_old_rules);
void reset() {
dealloc(m_old_rules);
m_old_rules = nullptr;
}
public:
restore_rules(rule_set& r): m_old_rules(alloc(rule_set, r)) {}
~restore_rules() override {}
void undo(context& ctx) override {
ctx.replace_rules(*m_old_rules);
reset();
@ -188,10 +188,8 @@ namespace datalog {
if (m_trail.get_num_scopes() == 0) {
throw default_exception("there are no backtracking points to pop to");
}
if (m_engine.get()) {
throw default_exception("pop operation is only supported by duality engine");
}
m_trail.pop_scope(1);
throw default_exception("pop operation is not supported");
m_trail.pop_scope(1);
}
// -----------------------------------
@ -205,7 +203,7 @@ namespace datalog {
m_register_engine(re),
m_fparams(fp),
m_params_ref(pa),
m_params(alloc(fixedpoint_params, m_params_ref)),
m_params(alloc(fp_params, m_params_ref)),
m_decl_util(m),
m_rewriter(m),
m_var_subst(m),
@ -237,7 +235,7 @@ namespace datalog {
context::~context() {
reset();
dealloc(m_params);
dealloc(m_params);
}
void context::reset() {
@ -293,14 +291,14 @@ namespace datalog {
bool context::similarity_compressor() const { return m_params->datalog_similarity_compressor(); }
unsigned context::similarity_compressor_threshold() const { return m_params->datalog_similarity_compressor_threshold(); }
unsigned context::soft_timeout() const { return m_fparams.m_timeout; }
unsigned context::initial_restart_timeout() const { return m_params->datalog_initial_restart_timeout(); }
unsigned context::initial_restart_timeout() const { return m_params->datalog_initial_restart_timeout(); }
bool context::generate_explanations() const { return m_params->datalog_generate_explanations(); }
bool context::explanations_on_relation_level() const { return m_params->datalog_explanations_on_relation_level(); }
bool context::magic_sets_for_queries() const { return m_params->datalog_magic_sets_for_queries(); }
symbol context::tab_selection() const { return m_params->tab_selection(); }
bool context::xform_coi() const { return m_params->xform_coi(); }
bool context::xform_slice() const { return m_params->xform_slice(); }
bool context::xform_bit_blast() const { return m_params->xform_bit_blast(); }
bool context::xform_bit_blast() const { return m_params->xform_bit_blast(); }
bool context::karr() const { return m_params->xform_karr(); }
bool context::scale() const { return m_params->xform_scale(); }
bool context::magic() const { return m_params->xform_magic(); }
@ -430,7 +428,7 @@ namespace datalog {
}
void context::set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
void context::set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
symbol const * relation_names) {
if (relation_name_cnt > 0) {
ensure_engine();
@ -440,9 +438,9 @@ namespace datalog {
}
}
func_decl * context::mk_fresh_head_predicate(symbol const & prefix, symbol const & suffix,
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 =
func_decl* new_pred =
m.mk_fresh_func_decl(prefix, suffix, arity, domain, m.mk_bool_sort());
register_predicate(new_pred, true);
@ -475,7 +473,7 @@ namespace datalog {
//
// 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 = nullptr;
@ -496,13 +494,13 @@ namespace datalog {
rule* old_rule = nullptr;
for (unsigned i = 0; i < size_before; ++i) {
if (rls[i]->name() == name) {
if (old_rule) {
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];
old_rule = rls[i];
}
}
if (old_rule) {
@ -558,7 +556,7 @@ namespace datalog {
ensure_engine();
m_engine->add_cover(level, pred, property);
}
void context::add_invariant(func_decl* pred, expr *property)
{
ensure_engine();
@ -568,34 +566,28 @@ namespace datalog {
void context::check_rules(rule_set& r) {
m_rule_properties.set_generate_proof(generate_proof_trace());
switch(get_engine()) {
case DATALOG_ENGINE:
case DATALOG_ENGINE:
m_rule_properties.collect(r);
m_rule_properties.check_quantifier_free();
m_rule_properties.check_uninterpreted_free();
m_rule_properties.check_nested_free();
m_rule_properties.check_nested_free();
m_rule_properties.check_infinite_sorts();
break;
case SPACER_ENGINE:
case PDR_ENGINE:
m_rule_properties.collect(r);
m_rule_properties.check_existential_tail();
m_rule_properties.check_for_negated_predicates();
m_rule_properties.check_uninterpreted_free();
break;
case QPDR_ENGINE:
m_rule_properties.collect(r);
m_rule_properties.check_for_negated_predicates();
m_rule_properties.check_uninterpreted_free();
break;
case BMC_ENGINE:
m_rule_properties.collect(r);
m_rule_properties.check_for_negated_predicates();
break;
break;
case QBMC_ENGINE:
m_rule_properties.collect(r);
m_rule_properties.check_existential_tail();
m_rule_properties.check_for_negated_predicates();
break;
break;
case TAB_ENGINE:
m_rule_properties.collect(r);
m_rule_properties.check_existential_tail();
@ -658,7 +650,7 @@ namespace datalog {
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;
@ -690,7 +682,7 @@ namespace datalog {
reopen();
}
}
void context::reopen() {
SASSERT(m_closed);
m_rule_set.reopen();
@ -703,7 +695,7 @@ namespace datalog {
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););
@ -732,7 +724,7 @@ namespace datalog {
}
void context::collect_params(param_descrs& p) {
fixedpoint_params::collect_param_descrs(p);
fp_params::collect_param_descrs(p);
insert_timeout(p);
}
@ -740,8 +732,8 @@ namespace datalog {
m_params_ref.copy(p);
if (m_engine.get()) m_engine->updt_params();
m_generate_proof_trace = m_params->generate_proof_trace();
m_unbound_compressor = m_params->datalog_unbound_compressor();
m_default_relation = m_params->datalog_default_relation();
m_unbound_compressor = m_params->datalog_unbound_compressor();
m_default_relation = m_params->datalog_default_relation();
}
expr_ref context::get_background_assertion() {
@ -756,7 +748,7 @@ namespace datalog {
void context::assert_expr(expr* e) {
TRACE("dl", tout << mk_ismt2_pp(e, m) << "\n";);
m_background.push_back(e);
m_background.push_back(e);
}
void context::cleanup() {
@ -776,19 +768,14 @@ namespace datalog {
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;
m_engine_type = SPACER_ENGINE;
}
else if (is_var(e) && m.is_bool(e)) {
m_engine_type = PDR_ENGINE;
m_engine_type = SPACER_ENGINE;
}
else if (dt.is_datatype(m.get_sort(e))) {
m_engine_type = PDR_ENGINE;
}
m_engine_type = SPACER_ENGINE;
}
}
};
@ -798,19 +785,13 @@ namespace datalog {
return;
}
symbol e = m_params->engine();
if (e == symbol("datalog")) {
m_engine_type = DATALOG_ENGINE;
}
else if (e == symbol("spacer")) {
m_engine_type = SPACER_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;
}
@ -830,7 +811,7 @@ namespace datalog {
if (m_engine_type == LAST_ENGINE) {
expr_fast_mark1 mark;
engine_type_proc proc(m);
m_engine_type = DATALOG_ENGINE;
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());
@ -858,8 +839,6 @@ namespace datalog {
switch (get_engine()) {
case DATALOG_ENGINE:
case SPACER_ENGINE:
case PDR_ENGINE:
case QPDR_ENGINE:
case BMC_ENGINE:
case QBMC_ENGINE:
case TAB_ENGINE:
@ -882,8 +861,6 @@ namespace datalog {
switch (get_engine()) {
case DATALOG_ENGINE:
case SPACER_ENGINE:
case PDR_ENGINE:
case QPDR_ENGINE:
case BMC_ENGINE:
case QBMC_ENGINE:
case TAB_ENGINE:
@ -916,15 +893,15 @@ namespace datalog {
m_rel = dynamic_cast<rel_context_base*>(m_engine.get());
}
}
}
}
lbool context::rel_query(unsigned num_rels, func_decl * const* rels) {
lbool context::rel_query(unsigned num_rels, func_decl * const* rels) {
m_last_answer = nullptr;
ensure_engine();
return m_engine->query(num_rels, rels);
}
expr* context::get_answer_as_formula() {
if (m_last_answer) {
return m_last_answer.get();
@ -977,7 +954,7 @@ namespace datalog {
void context::display(std::ostream & out) const {
display_rules(out);
if (m_rel) m_rel->display_facts(out);
if (m_rel) m_rel->display_facts(out);
}
void context::display_profile(std::ostream& out) const {
@ -1013,10 +990,10 @@ namespace datalog {
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.
static void collect_free_funcs(unsigned sz, expr* const* exprs,
static void collect_free_funcs(unsigned sz, expr* const* exprs,
ast_pp_util& v,
mk_fresh_name& fresh_names) {
v.collect(sz, exprs);
@ -1028,7 +1005,7 @@ namespace datalog {
fresh_names.add(e);
}
}
void context::get_raw_rule_formulas(expr_ref_vector& rules, svector<symbol>& names, unsigned_vector &bounds) {
for (unsigned i = 0; i < m_rule_fmls.size(); ++i) {
expr_ref r = bind_vars(m_rule_fmls[i].get(), true);
@ -1041,7 +1018,7 @@ namespace datalog {
void context::get_rules_as_formulas(expr_ref_vector& rules, expr_ref_vector& queries, svector<symbol>& names) {
expr_ref fml(m);
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) {
m_free_vars(m_rule_fmls[i].get());
@ -1090,7 +1067,7 @@ namespace datalog {
}
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]);
names.push_back(m_rule_names[i]);
}
}
@ -1103,7 +1080,7 @@ namespace datalog {
}
return out;
}
void context::display_smt2(unsigned num_queries, expr* const* qs, std::ostream& out) {
ast_manager& m = get_manager();
ast_pp_util visitor(m);
@ -1132,7 +1109,7 @@ namespace datalog {
for (unsigned i = 0; i < sz; ++i) {
func_decl* f = visitor.coll.get_func_decls()[i];
if (f->get_family_id() != null_family_id) {
//
//
}
else if (is_predicate(f) && use_fixedpoint_extensions) {
rels.insert(f);
@ -1145,12 +1122,12 @@ namespace datalog {
if (!use_fixedpoint_extensions) {
out << "(set-logic HORN)\n";
}
for (func_decl * f : rels)
for (func_decl * f : rels)
visitor.remove_decl(f);
visitor.display_decls(out);
for (func_decl * f : rels)
for (func_decl * f : rels)
display_rel_decl(out, f);
if (use_fixedpoint_extensions && do_declare_vars) {
@ -1166,7 +1143,7 @@ namespace datalog {
PP(axioms[i]);
out << ")\n";
}
for (unsigned i = 0; i < rules.size(); ++i) {
for (unsigned i = 0; i < rules.size(); ++i) {
out << (use_fixedpoint_extensions?"(rule ":"(assert ");
expr* r = rules[i].get();
symbol nm = names[i];
@ -1179,7 +1156,7 @@ namespace datalog {
while (fresh_names.contains(nm)) {
std::ostringstream s;
s << nm << "!";
nm = symbol(s.str().c_str());
nm = symbol(s.str().c_str());
}
fresh_names.add(nm);
display_symbol(out, nm) << ")";
@ -1205,7 +1182,7 @@ namespace datalog {
args.push_back(m.mk_var(j, m_free_vars[j]));
}
qfn = m.mk_implies(q, m.mk_app(fn, args.size(), args.c_ptr()));
out << "(assert ";
PP(qfn);
out << ")\n";
@ -1232,7 +1209,7 @@ namespace datalog {
smt2_pp_environment_dbg env(m);
out << "(declare-rel ";
display_symbol(out, f->get_name()) << " (";
for (unsigned i = 0; i < f->get_arity(); ++i) {
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 << " ";
@ -1262,12 +1239,12 @@ namespace datalog {
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
// 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;
@ -1280,7 +1257,7 @@ namespace datalog {
quantifier* q = to_quantifier(r);
if (!q->is_forall()) {
continue;
}
}
if (has_quantifiers(q->get_expr())) {
continue;
}
@ -1310,7 +1287,7 @@ namespace datalog {
fresh_vars.push_back(m.mk_const(name, s));
out << "(declare-var " << name << " ";
ast_smt2_pp(out, s, env);
out << ")\n";
out << ")\n";
}
subst.push_back(fresh_vars[vars[max_var]].get());
}
@ -1322,4 +1299,3 @@ namespace datalog {
};

76
src/muz/base/dl_context.h
View file

@ -44,7 +44,7 @@ Revision History:
#include "muz/base/bind_variables.h"
#include "muz/base/rule_properties.h"
struct fixedpoint_params;
struct fp_params;
namespace datalog {
@ -98,7 +98,7 @@ namespace datalog {
relation_fact(ast_manager & m) : app_ref_vector(m) {}
relation_fact(ast_manager & m, unsigned sz) : app_ref_vector(m) { resize(sz); }
relation_fact(context & ctx);
iterator begin() const { return c_ptr(); }
iterator end() const { return c_ptr()+size(); }
@ -126,7 +126,7 @@ namespace datalog {
virtual bool has_facts(func_decl * pred) const = 0;
virtual void store_relation(func_decl * pred, relation_base * rel) = 0;
virtual void inherit_predicate_kind(func_decl* new_pred, func_decl* orig_pred) = 0;
virtual void set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
virtual void set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
symbol const * relation_names) = 0;
virtual bool output_profile() const = 0;
virtual void collect_non_empty_predicates(func_decl_set& preds) = 0;
@ -147,7 +147,7 @@ namespace datalog {
public:
contains_pred(context& ctx): ctx(ctx) {}
~contains_pred() override {}
bool operator()(expr* e) override {
return ctx.is_predicate(e);
}
@ -170,7 +170,7 @@ namespace datalog {
register_engine_base& m_register_engine;
smt_params & m_fparams;
params_ref m_params_ref;
fixedpoint_params* m_params;
fp_params* m_params;
bool m_generate_proof_trace; // cached configuration parameter
bool m_unbound_compressor; // cached configuration parameter
symbol m_default_relation; // cached configuration parameter
@ -227,7 +227,7 @@ namespace datalog {
void push();
void pop();
bool saturation_was_run() const { return m_saturation_was_run; }
void notify_saturation_was_run() { m_saturation_was_run = true; }
@ -236,7 +236,7 @@ namespace datalog {
ast_manager & get_manager() const { return m; }
rule_manager & get_rule_manager() { return m_rule_manager; }
smt_params & get_fparams() const { return m_fparams; }
fixedpoint_params const& get_params() const { return *m_params; }
fp_params const& get_params() const { return *m_params; }
DL_ENGINE get_engine() { configure_engine(); return m_engine_type; }
register_engine_base& get_register_engine() { return m_register_engine; }
th_rewriter& get_rewriter() { return m_rewriter; }
@ -251,7 +251,7 @@ namespace datalog {
symbol default_table() const;
symbol default_relation() const;
void set_default_relation(symbol const& s);
symbol default_table_checker() const;
symbol default_table_checker() const;
symbol check_relation() const;
bool default_table_checked() const;
bool dbg_fpr_nonempty_relation_signature() const;
@ -275,7 +275,7 @@ namespace datalog {
bool compress_unbound() const;
bool quantify_arrays() const;
bool instantiate_quantifiers() const;
bool xform_bit_blast() const;
bool xform_bit_blast() const;
bool xform_slice() const;
bool xform_coi() const;
bool array_blast() const;
@ -291,9 +291,9 @@ namespace datalog {
void register_variable(func_decl* var);
/*
Replace constants that have been registered as
Replace constants that have been registered as
variables by de-Bruijn indices and corresponding
universal (if is_forall is true) or existential
universal (if is_forall is true) or existential
quantifier.
*/
expr_ref bind_vars(expr* fml, bool is_forall);
@ -303,7 +303,7 @@ namespace datalog {
/**
Register datalog relation.
If named is true, we associate the predicate with its name, so that it can be
If named is true, we associate the predicate with its name, so that it can be
retrieved by the try_get_predicate_decl() function. Auxiliary predicates introduced
e.g. by rule transformations do not need to be named.
*/
@ -326,7 +326,7 @@ namespace datalog {
/**
\brief If a predicate name has a \c func_decl object assigned, return pointer to it;
otherwise return 0.
Not all \c func_decl object used as relation identifiers need to be assigned to their
names. Generally, the names coming from the parses are registered here.
*/
@ -334,13 +334,13 @@ namespace datalog {
func_decl * res = nullptr;
m_preds_by_name.find(pred_name, res);
return res;
}
}
/**
\brief Create a fresh head predicate declaration.
*/
func_decl * mk_fresh_head_predicate(symbol const & prefix, symbol const & suffix,
func_decl * mk_fresh_head_predicate(symbol const & prefix, symbol const & suffix,
unsigned arity, sort * const * domain, func_decl* orig_pred=nullptr);
@ -365,13 +365,13 @@ namespace datalog {
/**
\brief Assign names of variables used in the declaration of a predicate.
These names are used when printing out the relations to make the output conform
These names are used when printing out the relations to make the output conform
to the one of bddbddb.
*/
void set_argument_names(const func_decl * pred, const svector<symbol> & var_names);
symbol get_argument_name(const func_decl * pred, unsigned arg_index);
void set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
void set_predicate_representation(func_decl * pred, unsigned relation_name_cnt,
symbol const * relation_names);
void set_output_predicate(func_decl * pred) { m_rule_set.set_output_predicate(pred); }
@ -385,9 +385,9 @@ namespace datalog {
void add_fact(func_decl * pred, const relation_fact & fact);
bool has_facts(func_decl * pred) const;
void add_rule(rule_ref& r);
void assert_expr(expr* e);
expr_ref get_background_assertion();
unsigned get_num_assertions() { return m_background.size(); }
@ -397,7 +397,7 @@ namespace datalog {
Method exposed from API for adding rules.
*/
void add_rule(expr* rl, symbol const& name, unsigned bound = UINT_MAX);
/**
Update a named rule.
@ -421,9 +421,9 @@ namespace datalog {
at 'level+1', 'level+2' etc, and include level=-1.
*/
expr_ref get_cover_delta(int level, func_decl* pred);
/**
Add a property of predicate 'pred' at 'level'.
Add a property of predicate 'pred' at 'level'.
It gets pushed forward when possible.
*/
void add_cover(int level, func_decl* pred, expr* property);
@ -432,7 +432,7 @@ namespace datalog {
Add an invariant of predicate 'pred'.
*/
void add_invariant (func_decl *pred, expr *property);
/**
\brief Check rule subsumption.
*/
@ -471,15 +471,15 @@ namespace datalog {
proof_converter_ref& get_proof_converter() { return m_pc; }
void add_proof_converter(proof_converter* pc) { m_pc = concat(m_pc.get(), pc); }
void transform_rules(rule_transformer& transf);
void transform_rules(rule_transformer& transf);
void transform_rules(rule_transformer::plugin* plugin);
void replace_rules(rule_set const& rs);
void record_transformed_rules();
void apply_default_transformation();
void apply_default_transformation();
void collect_params(param_descrs& r);
void updt_params(params_ref const& p);
void display_rules(std::ostream & out) const {
@ -507,7 +507,7 @@ namespace datalog {
/**
\brief check if query 'q' is satisfied under asserted rules and background.
If successful, return OK and into \c result assign a relation with all
If successful, return OK and into \c result assign a relation with all
tuples matching the query. Otherwise return reason for failure and do not modify
\c result.
@ -515,7 +515,7 @@ namespace datalog {
starting from zero.
The caller becomes an owner of the relation object returned in \c result. The
relation object, however, should not outlive the datalog context since it is
relation object, however, should not outlive the datalog context since it is
linked to a relation plugin in the context.
*/
@ -524,7 +524,7 @@ namespace datalog {
lbool query_from_lvl (expr* q, unsigned lvl);
/**
\brief retrieve model from inductive invariant that shows query is unsat.
\pre engine == 'pdr' || engine == 'duality' - this option is only supported
for PDR mode and Duality mode.
*/
@ -532,7 +532,7 @@ namespace datalog {
/**
\brief retrieve proof from derivation of the query.
\pre engine == 'pdr' || engine == 'duality'- this option is only supported
for PDR mode and Duality mode.
*/
@ -588,12 +588,25 @@ namespace datalog {
rel_context_base* get_rel_context() { ensure_engine(); return m_rel; }
void add_callback(void *state,
const datalog::t_new_lemma_eh new_lemma_eh,
const datalog::t_predecessor_eh predecessor_eh,
const datalog::t_unfold_eh unfold_eh) {
ensure_engine();
m_engine->add_callback(state, new_lemma_eh, predecessor_eh, unfold_eh);
}
void add_constraint (expr *c, unsigned lvl){
ensure_engine();
m_engine->add_constraint(c, lvl);
}
private:
/**
Just reset all tables.
*/
void reset_tables();
void reset_tables();
void flush_add_rules();
@ -614,4 +627,3 @@ namespace datalog {
};
#endif /* DL_CONTEXT_H_ */

15
src/muz/base/dl_engine_base.h
View file

@ -25,9 +25,7 @@ Revision History:
namespace datalog {
enum DL_ENGINE {
DATALOG_ENGINE,
PDR_ENGINE,
SPACER_ENGINE,
QPDR_ENGINE,
BMC_ENGINE,
QBMC_ENGINE,
TAB_ENGINE,
@ -36,6 +34,10 @@ namespace datalog {
LAST_ENGINE
};
typedef void (*t_new_lemma_eh)(void *state, expr *lemma, unsigned level);
typedef void (*t_predecessor_eh)(void *state);
typedef void (*t_unfold_eh)(void *state);
class engine_base {
ast_manager& m;
std::string m_name;
@ -102,6 +104,15 @@ namespace datalog {
virtual proof_ref get_proof() {
return proof_ref(m.mk_asserted(m.mk_true()), m);
}
virtual void add_callback(void *state,
const t_new_lemma_eh new_lemma_eh,
const t_predecessor_eh predecessor_eh,
const t_unfold_eh unfold_eh) {
throw default_exception(std::string("add_lemma_exchange_callbacks is not supported for ") + m_name);
}
virtual void add_constraint (expr *c, unsigned lvl){
throw default_exception(std::string("add_constraint is not supported for ") + m_name);
}
virtual void updt_params() {}
virtual void cancel() {}
virtual void cleanup() {}

213
src/muz/base/fixedpoint_params.pyg → src/muz/base/fp_params.pyg
View file

@ -1,37 +1,37 @@
def_module_params('fixedpoint',
def_module_params('fp',
description='fixedpoint parameters',
export=True,
params=(('timeout', UINT, UINT_MAX, 'set timeout'),
('engine', SYMBOL, 'auto-config',
'Select: auto-config, datalog, spacer, pdr, bmc'),
('datalog.default_table', SYMBOL, 'sparse',
('engine', SYMBOL, 'auto-config',
'Select: auto-config, datalog, bmc, spacer'),
('datalog.default_table', SYMBOL, 'sparse',
'default table implementation: sparse, hashtable, bitvector, interval'),
('datalog.default_relation', SYMBOL, 'pentagon',
('datalog.default_relation', SYMBOL, 'pentagon',
'default relation implementation: external_relation, pentagon'),
('datalog.generate_explanations', BOOL, False,
('datalog.generate_explanations', BOOL, False,
'produce explanations for produced facts when using the datalog engine'),
('datalog.use_map_names', BOOL, True,
('datalog.use_map_names', BOOL, True,
"use names from map files when displaying tuples"),
('datalog.magic_sets_for_queries', BOOL, False,
('datalog.magic_sets_for_queries', BOOL, False,
"magic set transformation will be used for queries"),
('datalog.explanations_on_relation_level', BOOL, False,
'if true, explanations are generated as history of each relation, ' +
'rather than per fact (generate_explanations must be set to true for ' +
('datalog.explanations_on_relation_level', BOOL, False,
'if true, explanations are generated as history of each relation, ' +
'rather than per fact (generate_explanations must be set to true for ' +
'this option to have any effect)'),
('datalog.unbound_compressor', BOOL, True,
"auxiliary relations will be introduced to avoid unbound variables " +
('datalog.unbound_compressor', BOOL, True,
"auxiliary relations will be introduced to avoid unbound variables " +
"in rule heads"),
('datalog.similarity_compressor', BOOL, True,
"rules that differ only in values of constants will be merged into " +
('datalog.similarity_compressor', BOOL, True,
"rules that differ only in values of constants will be merged into " +
"a single rule"),
('datalog.similarity_compressor_threshold', UINT, 11,
"if similarity_compressor is on, this value determines how many " +
('datalog.similarity_compressor_threshold', UINT, 11,
"if similarity_compressor is on, this value determines how many " +
"similar rules there must be in order for them to be merged"),
('datalog.all_or_nothing_deltas', BOOL, False,
('datalog.all_or_nothing_deltas', BOOL, False,
"compile rules so that it is enough for the delta relation in " +
"union and widening operations to determine only whether the " +
"union and widening operations to determine only whether the " +
"updated relation was modified or not"),
('datalog.compile_with_widening', BOOL, False,
('datalog.compile_with_widening', BOOL, False,
"widening will be used to compile recursive rules"),
('datalog.default_table_checked', BOOL, False, "if true, the default " +
'table will be default_table inside a wrapper that checks that its results ' +
@ -39,15 +39,15 @@ def_module_params('fixedpoint',
('datalog.default_table_checker', SYMBOL, 'null', "see default_table_checked"),
('datalog.check_relation',SYMBOL,'null', "name of default relation to check. " +
"operations on the default relation will be verified using SMT solving"),
('datalog.initial_restart_timeout', UINT, 0,
"length of saturation run before the first restart (in ms), " +
('datalog.initial_restart_timeout', UINT, 0,
"length of saturation run before the first restart (in ms), " +
"zero means no restarts"),
('datalog.output_profile', BOOL, False,
"determines whether profile information should be " +
('datalog.output_profile', BOOL, False,
"determines whether profile information should be " +
"output when outputting Datalog rules or instructions"),
('datalog.print.tuples', BOOL, True,
('datalog.print.tuples', BOOL, True,
"determines whether tuples for output predicates should be output"),
('datalog.profile_timeout_milliseconds', UINT, 0,
('datalog.profile_timeout_milliseconds', UINT, 0,
"instructions and rules that took less than the threshold " +
"will not be printed when printed the instruction/rule list"),
('datalog.dbg_fpr_nonempty_relation_signature', BOOL, False,
@ -56,139 +56,126 @@ def_module_params('fixedpoint',
"table columns, if it would have been empty otherwise"),
('datalog.subsumption', BOOL, True,
"if true, removes/filters predicates with total transitions"),
('pdr.bfs_model_search', BOOL, True,
"use BFS strategy for expanding model search"),
('pdr.farkas', BOOL, True,
"use lemma generator based on Farkas (for linear real arithmetic)"),
('generate_proof_trace', BOOL, False, "trace for 'sat' answer as proof object"),
('pdr.flexible_trace', BOOL, False,
"allow PDR generate long counter-examples " +
"by extending candidate trace within search area"),
('pdr.flexible_trace_depth', UINT, UINT_MAX,
'Controls the depth (below the current level) at which flexible trace can be applied'),
('pdr.use_model_generalizer', BOOL, False,
"use model for backwards propagation (instead of symbolic simulation)"),
('pdr.validate_result', BOOL, False,
('spacer.push_pob', BOOL, False, "push blocked pobs to higher level"),
('spacer.push_pob_max_depth', UINT, UINT_MAX,
'Maximum depth at which push_pob is enabled'),
('validate', BOOL, False,
"validate result (by proof checking or model checking)"),
('pdr.simplify_formulas_pre', BOOL, False,
"simplify derived formulas before inductive propagation"),
('pdr.simplify_formulas_post', BOOL, False,
"simplify derived formulas after inductive propagation"),
('pdr.use_multicore_generalizer', BOOL, False,
"extract multiple cores for blocking states"),
('pdr.use_inductive_generalizer', BOOL, True,
('spacer.simplify_lemmas_pre', BOOL, False,
"simplify derived lemmas before inductive propagation"),
('spacer.simplify_lemmas_post', BOOL, False,
"simplify derived lemmas after inductive propagation"),
('spacer.use_inductive_generalizer', BOOL, True,
"generalize lemmas using induction strengthening"),
('pdr.use_arith_inductive_generalizer', BOOL, False,
"generalize lemmas using arithmetic heuristics for induction strengthening"),
('pdr.use_convex_closure_generalizer', BOOL, False,
"generalize using convex closures of lemmas"),
('pdr.use_convex_interior_generalizer', BOOL, False,
"generalize using convex interiors of lemmas"),
('pdr.cache_mode', UINT, 0, "use no (0), symbolic (1) or explicit " +
"cache (2) for model search"),
('pdr.inductive_reachability_check', BOOL, False,
"assume negation of the cube on the previous level when " +
"checking for reachability (not only during cube weakening)"),
('pdr.max_num_contexts', UINT, 500, "maximal number of contexts to create"),
('pdr.try_minimize_core', BOOL, False,
"try to reduce core size (before inductive minimization)"),
('pdr.utvpi', BOOL, True, 'Enable UTVPI strategy'),
('print_fixedpoint_extensions', BOOL, True,
"use SMT-LIB2 fixedpoint extensions, instead of pure SMT2, " +
('spacer.max_num_contexts', UINT, 500, "maximal number of contexts to create"),
('print_fixedpoint_extensions', BOOL, True,
"use SMT-LIB2 fixedpoint extensions, instead of pure SMT2, " +
"when printing rules"),
('print_low_level_smt2', BOOL, False,
"use (faster) low-level SMT2 printer (the printer is scalable " +
('print_low_level_smt2', BOOL, False,
"use (faster) low-level SMT2 printer (the printer is scalable " +
"but the result may not be as readable)"),
('print_with_variable_declarations', BOOL, True,
('print_with_variable_declarations', BOOL, True,
"use variable declarations when displaying rules " +
"(instead of attempting to use original names)"),
('print_answer', BOOL, False, 'print answer instance(s) to query'),
('print_certificate', BOOL, False,
('print_certificate', BOOL, False,
'print certificate for reachability or non-reachability'),
('print_boogie_certificate', BOOL, False,
('print_boogie_certificate', BOOL, False,
'print certificate for reachability or non-reachability using a ' +
'format understood by Boogie'),
('print_statistics', BOOL, False, 'print statistics'),
('print_aig', SYMBOL, '',
('print_aig', SYMBOL, '',
'Dump clauses in AIG text format (AAG) to the given file name'),
('tab.selection', SYMBOL, 'weight',
('tab.selection', SYMBOL, 'weight',
'selection method for tabular strategy: weight (default), first, var-use'),
('xform.bit_blast', BOOL, False,
('xform.bit_blast', BOOL, False,
'bit-blast bit-vectors'),
('xform.magic', BOOL, False,
('xform.magic', BOOL, False,
"perform symbolic magic set transformation"),
('xform.scale', BOOL, False,
('xform.scale', BOOL, False,
"add scaling variable to linear real arithmetic clauses"),
('xform.inline_linear', BOOL, True, "try linear inlining method"),
('xform.inline_eager', BOOL, True, "try eager inlining of rules"),
('xform.inline_linear_branch', BOOL, False,
('xform.inline_linear_branch', BOOL, False,
"try linear inlining method with potential expansion"),
('xform.compress_unbound', BOOL, True, "compress tails with unbound variables"),
('xform.fix_unbound_vars', BOOL, False, "fix unbound variables in tail"),
('xform.unfold_rules', UINT, 0,
"unfold rules statically using iterative squarring"),
('xform.unfold_rules', UINT, 0,
"unfold rules statically using iterative squaring"),
('xform.slice', BOOL, True, "simplify clause set using slicing"),
('xform.karr', BOOL, False,
('xform.karr', BOOL, False,
"Add linear invariants to clauses using Karr's method"),
('spacer.use_eqclass', BOOL, False, "Generalizes equalities to equivalence classes"),
('xform.transform_arrays', BOOL, False,
('spacer.use_euf_gen', BOOL, False, 'Generalize lemmas and pobs using implied equalities'),
('xform.transform_arrays', BOOL, False,
"Rewrites arrays equalities and applies select over store"),
('xform.instantiate_arrays', BOOL, False,
('xform.instantiate_arrays', BOOL, False,
"Transforms P(a) into P(i, a[i] a)"),
('xform.instantiate_arrays.enforce', BOOL, False,
('xform.instantiate_arrays.enforce', BOOL, False,
"Transforms P(a) into P(i, a[i]), discards a from predicate"),
('xform.instantiate_arrays.nb_quantifier', UINT, 1,
('xform.instantiate_arrays.nb_quantifier', UINT, 1,
"Gives the number of quantifiers per array"),
('xform.instantiate_arrays.slice_technique', SYMBOL, "no-slicing",
('xform.instantiate_arrays.slice_technique', SYMBOL, "no-slicing",
"<no-slicing>=> GetId(i) = i, <smash> => GetId(i) = true"),
('xform.quantify_arrays', BOOL, False,
('xform.quantify_arrays', BOOL, False,
"create quantified Horn clauses from clauses with arrays"),
('xform.instantiate_quantifiers', BOOL, False,
('xform.instantiate_quantifiers', BOOL, False,
"instantiate quantified Horn clauses using E-matching heuristic"),
('xform.coalesce_rules', BOOL, False, "coalesce rules"),
('xform.tail_simplifier_pve', BOOL, True, "propagate_variable_equivalences"),
('xform.subsumption_checker', BOOL, True, "Enable subsumption checker (no support for model conversion)"),
('xform.coi', BOOL, True, "use cone of influence simplification"),
('spacer.order_children', UINT, 0, 'SPACER: order of enqueuing children in non-linear rules : 0 (original), 1 (reverse)'),
('spacer.eager_reach_check', BOOL, True, 'SPACER: eagerly check if a query is reachable using reachability facts of predecessors'),
('spacer.order_children', UINT, 0, 'SPACER: order of enqueuing children in non-linear rules : 0 (original), 1 (reverse), 2 (random)'),
('spacer.use_lemma_as_cti', BOOL, False, 'SPACER: use a lemma instead of a CTI in flexible_trace'),
('spacer.reset_obligation_queue', BOOL, True, 'SPACER: reset obligation queue when entering a new level'),
('spacer.init_reach_facts', BOOL, True, 'SPACER: initialize reachability facts with false'),
('spacer.reset_pob_queue', BOOL, True, 'SPACER: reset pob obligation queue when entering a new level'),
('spacer.use_array_eq_generalizer', BOOL, True, 'SPACER: attempt to generalize lemmas with array equalities'),
('spacer.use_derivations', BOOL, True, 'SPACER: using derivation mechanism to cache intermediate results for non-linear rules'),
('xform.array_blast', BOOL, False, "try to eliminate local array terms using Ackermannization -- some array terms may remain"),
('xform.array_blast_full', BOOL, False, "eliminate all local array variables by QE"),
('spacer.skip_propagate', BOOL, False, "Skip propagate/pushing phase. Turns PDR into a BMC that returns either reachable or unknown"),
('spacer.use_derivations', BOOL, True, 'SPACER: using derivation mechanism to cache intermediate results for non-linear rules'),
('xform.array_blast', BOOL, False, "try to eliminate local array terms using Ackermannization -- some array terms may remain"),
('xform.array_blast_full', BOOL, False, "eliminate all local array variables by QE"),
('spacer.propagate', BOOL, True, 'Enable propagate/pushing phase'),
('spacer.max_level', UINT, UINT_MAX, "Maximum level to explore"),
('spacer.elim_aux', BOOL, True, "Eliminate auxiliary variables in reachability facts"),
('spacer.reach_as_init', BOOL, True, "Extend initial rules with computed reachability facts"),
('spacer.blast_term_ite', BOOL, True, "Expand non-Boolean ite-terms"),
('spacer.nondet_tie_break', BOOL, False, "Break ties in obligation queue non-deterministically"),
('spacer.reach_dnf', BOOL, True, "Restrict reachability facts to DNF"),
('bmc.linear_unrolling_depth', UINT, UINT_MAX, "Maximal level to explore"),
('spacer.split_farkas_literals', BOOL, False, "Split Farkas literals"),
('spacer.native_mbp', BOOL, False, "Use native mbp of Z3"),
('spacer.iuc.split_farkas_literals', BOOL, False, "Split Farkas literals"),
('spacer.native_mbp', BOOL, True, "Use native mbp of Z3"),
('spacer.eq_prop', BOOL, True, "Enable equality and bound propagation in arithmetic"),
('spacer.weak_abs', BOOL, True, "Weak abstraction"),
('spacer.restarts', BOOL, False, "Enable reseting obligation queue"),
('spacer.restart_initial_threshold', UINT, 10, "Intial threshold for restarts"),
('spacer.random_seed', UINT, 0, "Random seed to be used by SMT solver"),
('spacer.ground_cti', BOOL, True, "Require CTI to be ground"),
('spacer.vs.dump_benchmarks', BOOL, False, 'dump benchmarks in virtual solver'),
('spacer.vs.dump_min_time', DOUBLE, 5.0, 'min time to dump benchmark'),
('spacer.vs.recheck', BOOL, False, 're-check locally during benchmark dumping'),
('spacer.mbqi', BOOL, True, 'use model-based quantifier instantiation'),
('spacer.mbqi', BOOL, True, 'Enable mbqi'),
('spacer.keep_proxy', BOOL, True, 'keep proxy variables (internal parameter)'),
('spacer.instantiate', BOOL, True, 'instantiate quantified lemmas'),
('spacer.qlemmas', BOOL, True, 'allow quantified lemmas in frames'),
('spacer.new_unsat_core', BOOL, True, 'use the new implementation of unsat-core-generation'),
('spacer.minimize_unsat_core', BOOL, False, 'compute unsat-core by min-cut'),
('spacer.farkas_optimized', BOOL, True, 'use the optimized farkas plugin, which performs gaussian elimination'),
('spacer.farkas_a_const', BOOL, True, 'if the unoptimized farkas plugin is used, use the constants from A while constructing unsat_cores'),
('spacer.lemma_sanity_check', BOOL, False, 'check during generalization whether lemma is actually correct'),
('spacer.reuse_pobs', BOOL, True, 'reuse POBs'),
('spacer.simplify_pob', BOOL, False, 'simplify POBs by removing redundant constraints')
('spacer.q3', BOOL, True, 'Allow quantified lemmas in frames'),
('spacer.q3.instantiate', BOOL, True, 'Instantiate quantified lemmas'),
('spacer.iuc', UINT, 1,
'0 = use old implementation of unsat-core-generation, ' +
'1 = use new implementation of IUC generation, ' +
'2 = use new implementation of IUC + min-cut optimization'),
('spacer.iuc.arith', UINT, 1,
'0 = use simple Farkas plugin, ' +
'1 = use simple Farkas plugin with constant from other partition (like old unsat-core-generation),' +
'2 = use Gaussian elimination optimization (broken), 3 = use additive IUC plugin'),
('spacer.iuc.old_hyp_reducer', BOOL, False, 'use old hyp reducer instead of new implementation, for debugging only'),
('spacer.validate_lemmas', BOOL, False, 'Validate each lemma after generalization'),
('spacer.reuse_pobs', BOOL, True, 'Reuse pobs'),
('spacer.ground_pobs', BOOL, True, 'Ground pobs by using values from a model'),
('spacer.iuc.print_farkas_stats', BOOL, False, 'prints for each proof how many Farkas lemmas it contains and how many of these participate in the cut (for debugging)'),
('spacer.iuc.debug_proof', BOOL, False, 'prints proof used by unsat-core-learner for debugging purposes (debugging)'),
('spacer.simplify_pob', BOOL, False, 'simplify pobs by removing redundant constraints'),
('spacer.q3.use_qgen', BOOL, False, 'use quantified lemma generalizer'),
('spacer.q3.qgen.normalize', BOOL, True, 'normalize cube before quantified generalization'),
('spacer.p3.share_lemmas', BOOL, False, 'Share frame lemmas'),
('spacer.p3.share_invariants', BOOL, False, "Share invariants lemmas"),
('spacer.min_level', UINT, 0, 'Minimal level to explore'),
('spacer.print_json', SYMBOL, '', 'Print pobs tree in JSON format to a given file'),
('spacer.ctp', BOOL, True, 'Enable counterexample-to-pushing'),
('spacer.use_inc_clause', BOOL, True, 'Use incremental clause to represent trans'),
('spacer.dump_benchmarks', BOOL, False, 'Dump SMT queries as benchmarks'),
('spacer.dump_threshold', DOUBLE, 5.0, 'Threshold in seconds on dumping benchmarks'),
('spacer.gpdr', BOOL, False, 'Use GPDR solving strategy for non-linear CHC'),
('spacer.gpdr.bfs', BOOL, True, 'Use BFS exploration strategy for expanding model search'),
))

6
src/muz/base/rule_properties.cpp
View file

@ -146,12 +146,10 @@ void rule_properties::check_existential_tail() {
else if (is_quantifier(e)) {
tocheck.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)) {
else if (m.is_eq(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)) {
else if (m.is_eq(e, e1, e2) && m.is_true(e2)) {
todo.push_back(e1);
}
else {

2
src/muz/bmc/dl_bmc_engine.cpp
View file

@ -33,7 +33,7 @@ Revision History:
#include "muz/transforms/dl_mk_rule_inliner.h"
#include "ast/scoped_proof.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
namespace datalog {

1
src/muz/fp/CMakeLists.txt
View file

@ -9,7 +9,6 @@ z3_add_component(fp
clp
ddnf
muz
pdr
rel
spacer
tab

68
src/muz/fp/dl_cmds.cpp
View file

@ -30,23 +30,23 @@ Notes:
#include "util/scoped_ctrl_c.h"
#include "util/scoped_timer.h"
#include "util/trail.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include<iomanip>
struct dl_context {
smt_params m_fparams;
params_ref m_params_ref;
fixedpoint_params m_params;
fp_params m_params;
cmd_context & m_cmd;
datalog::register_engine m_register_engine;
dl_collected_cmds* m_collected_cmds;
unsigned m_ref_count;
datalog::dl_decl_plugin* m_decl_plugin;
scoped_ptr<datalog::context> m_context;
scoped_ptr<datalog::context> m_context;
trail_stack<dl_context> m_trail;
fixedpoint_params const& get_params() {
fp_params const& get_params() {
init();
return m_context->get_params();
}
@ -58,18 +58,18 @@ struct dl_context {
m_ref_count(0),
m_decl_plugin(nullptr),
m_trail(*this) {}
void inc_ref() {
++m_ref_count;
}
void dec_ref() {
--m_ref_count;
if (0 == m_ref_count) {
dealloc(this);
}
}
void init() {
ast_manager& m = m_cmd.m();
if (!m_context) {
@ -83,10 +83,10 @@ struct dl_context {
else {
m_decl_plugin = alloc(datalog::dl_decl_plugin);
m.register_plugin(symbol("datalog_relation"), m_decl_plugin);
}
}
}
}
void reset() {
m_context = nullptr;
}
@ -97,9 +97,9 @@ struct dl_context {
m_trail.push(push_back_vector<dl_context, func_decl_ref_vector>(m_collected_cmds->m_rels));
}
dlctx().register_predicate(pred, false);
dlctx().set_predicate_representation(pred, num_kinds, kinds);
dlctx().set_predicate_representation(pred, num_kinds, kinds);
}
void add_rule(expr * rule, symbol const& name, unsigned bound) {
init();
if (m_collected_cmds) {
@ -112,7 +112,7 @@ struct dl_context {
else {
m_context->add_rule(rule, name, bound);
}
}
}
bool collect_query(func_decl* q) {
if (m_collected_cmds) {
@ -127,7 +127,7 @@ struct dl_context {
m_collected_cmds->m_queries.push_back(qr);
m_trail.push(push_back_vector<dl_context, expr_ref_vector>(m_collected_cmds->m_queries));
return true;
}
}
else {
return false;
}
@ -142,7 +142,7 @@ struct dl_context {
m_trail.pop_scope(1);
dlctx().pop();
}
datalog::context & dlctx() {
init();
return *m_context;
@ -162,7 +162,7 @@ class dl_rule_cmd : public cmd {
public:
dl_rule_cmd(dl_context * dl_ctx):
cmd("rule"),
m_dl_ctx(dl_ctx),
m_dl_ctx(dl_ctx),
m_arg_idx(0),
m_t(nullptr),
m_bound(UINT_MAX) {}
@ -210,7 +210,7 @@ public:
}
char const * get_usage() const override { return "predicate"; }
char const * get_main_descr() const override {
return "pose a query to a predicate based on the Horn rules.";
return "pose a query to a predicate based on the Horn rules.";
}
cmd_arg_kind next_arg_kind(cmd_context & ctx) const override {
@ -243,9 +243,9 @@ public:
return;
}
datalog::context& dlctx = m_dl_ctx->dlctx();
set_background(ctx);
set_background(ctx);
dlctx.updt_params(m_params);
unsigned timeout = m_dl_ctx->get_params().timeout();
unsigned timeout = m_dl_ctx->get_params().timeout();
cancel_eh<reslimit> eh(ctx.m().limit());
bool query_exn = false;
lbool status = l_undef;
@ -271,12 +271,12 @@ public:
ctx.regular_stream() << "unsat\n";
print_certificate(ctx);
break;
case l_true:
case l_true:
ctx.regular_stream() << "sat\n";
print_answer(ctx);
print_certificate(ctx);
break;
case l_undef:
case l_undef:
if (dlctx.get_status() == datalog::BOUNDED){
ctx.regular_stream() << "bounded\n";
print_certificate(ctx);
@ -287,7 +287,7 @@ public:
case datalog::INPUT_ERROR:
ctx.regular_stream() << "input error\n";
break;
case datalog::MEMOUT:
ctx.regular_stream() << "memory bounds exceeded\n";
break;
@ -295,12 +295,12 @@ public:
case datalog::TIMEOUT:
ctx.regular_stream() << "timeout\n";
break;
case datalog::APPROX:
ctx.regular_stream() << "approximated relations\n";
break;
case datalog::OK:
case datalog::OK:
(void)query_exn;
SASSERT(query_exn);
break;
@ -324,7 +324,7 @@ public:
void init_pdescrs(cmd_context & ctx, param_descrs & p) override {
m_dl_ctx->dlctx().collect_params(p);
}
private:
void set_background(cmd_context& ctx) {
@ -356,8 +356,8 @@ private:
statistics st;
datalog::context& dlctx = m_dl_ctx->dlctx();
dlctx.collect_statistics(st);
st.update("time", ctx.get_seconds());
st.display_smt2(ctx.regular_stream());
st.update("time", ctx.get_seconds());
st.display_smt2(ctx.regular_stream());
}
}
@ -391,8 +391,8 @@ public:
void prepare(cmd_context & ctx) override {
ctx.m(); // ensure manager is initialized.
m_arg_idx = 0;
m_query_arg_idx = 0;
m_arg_idx = 0;
m_query_arg_idx = 0;
m_domain.reset();
m_kinds.reset();
}
@ -443,21 +443,21 @@ public:
m_arg_idx(0),
m_dl_ctx(dl_ctx)
{}
char const * get_usage() const override { return "<symbol> <sort>"; }
char const * get_descr(cmd_context & ctx) const override { return "declare constant as variable"; }
unsigned get_arity() const override { return 2; }
void prepare(cmd_context & ctx) override {
ctx.m(); // ensure manager is initialized.
m_arg_idx = 0;
m_arg_idx = 0;
}
cmd_arg_kind next_arg_kind(cmd_context & ctx) const override {
SASSERT(m_arg_idx <= 1);
if (m_arg_idx == 0) {
return CPK_SYMBOL;
return CPK_SYMBOL;
}
return CPK_SORT;
return CPK_SORT;
}
void set_next_arg(cmd_context & ctx, sort* s) override {
@ -466,7 +466,7 @@ public:
}
void set_next_arg(cmd_context & ctx, symbol const & s) override {
m_var_name = s;
m_var_name = s;
++m_arg_idx;
}
@ -523,7 +523,7 @@ static void install_dl_cmds_aux(cmd_context& ctx, dl_collected_cmds* collected_c
ctx.insert(alloc(dl_query_cmd, dl_ctx));
ctx.insert(alloc(dl_declare_rel_cmd, dl_ctx));
ctx.insert(alloc(dl_declare_var_cmd, dl_ctx));
ctx.insert(alloc(dl_push_cmd, dl_ctx));
ctx.insert(alloc(dl_push_cmd, dl_ctx));
ctx.insert(alloc(dl_pop_cmd, dl_ctx));
}

4
src/muz/fp/dl_register_engine.cpp
View file

@ -21,7 +21,6 @@ Revision History:
#include "muz/clp/clp_context.h"
#include "muz/tab/tab_context.h"
#include "muz/rel/rel_context.h"
#include "muz/pdr/pdr_dl_interface.h"
#include "muz/ddnf/ddnf.h"
#include "muz/spacer/spacer_dl_interface.h"
@ -30,9 +29,6 @@ namespace datalog {
engine_base* register_engine::mk_engine(DL_ENGINE engine_type) {
switch(engine_type) {
case PDR_ENGINE:
case QPDR_ENGINE:
return alloc(pdr::dl_interface, *m_ctx);
case SPACER_ENGINE:
return alloc(spacer::dl_interface, *m_ctx);
case DATALOG_ENGINE:

59
src/muz/fp/horn_tactic.cpp
View file

@ -27,7 +27,7 @@ Revision History:
#include "muz/transforms/dl_mk_slice.h"
#include "tactic/generic_model_converter.h"
#include "muz/transforms/dl_transforms.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include "ast/ast_util.h"
#include "ast/rewriter/var_subst.h"
@ -71,7 +71,7 @@ class horn_tactic : public tactic {
f = to_quantifier(f)->get_expr();
}
else if (is_exists(f) && !is_positive) {
f = to_quantifier(f)->get_expr();
f = to_quantifier(f)->get_expr();
}
else if (m.is_not(f, e)) {
is_positive = !is_positive;
@ -84,7 +84,7 @@ class horn_tactic : public tactic {
if (!is_positive) {
f = m.mk_not(f);
}
}
bool is_predicate(expr* a) {
@ -144,7 +144,7 @@ class horn_tactic : public tactic {
expr* a = nullptr, *a1 = nullptr;
flatten_or(tmp, args);
for (unsigned i = 0; i < args.size(); ++i) {
a = args[i].get();
a = args[i].get();
check_predicate(mark, a);
if (m.is_not(a, a1)) {
body.push_back(a1);
@ -176,13 +176,13 @@ class horn_tactic : public tactic {
return expr_ref(m.mk_implies(body, head), m);
}
void operator()(goal_ref const & g,
void operator()(goal_ref const & g,
goal_ref_buffer & result) {
SASSERT(g->is_well_sorted());
tactic_report report("horn", *g);
bool produce_proofs = g->proofs_enabled();
if (produce_proofs) {
if (produce_proofs) {
if (!m_ctx.generate_proof_trace()) {
params_ref params = m_ctx.get_params().p;
params.set_bool("generate_proof_trace", true);
@ -208,7 +208,7 @@ class horn_tactic : public tactic {
case IS_QUERY:
queries.push_back(f);
break;
default:
default:
msg << "formula is not in Horn fragment: " << mk_pp(g->form(i), m) << "\n";
TRACE("horn", tout << msg.str(););
throw tactic_exception(msg.str().c_str());
@ -243,10 +243,10 @@ class horn_tactic : public tactic {
g->set(mc.get());
}
void verify(expr* q,
void verify(expr* q,
goal_ref const& g,
goal_ref_buffer & result,
model_converter_ref & mc,
goal_ref_buffer & result,
model_converter_ref & mc,
proof_converter_ref & pc) {
lbool is_reachable = l_undef;
@ -275,9 +275,9 @@ class horn_tactic : public tactic {
else {
g->assert_expr(m.mk_false());
}
break;
break;
}
case l_false: {
case l_false: {
// goal is sat
g->reset();
if (produce_models) {
@ -290,11 +290,11 @@ class horn_tactic : public tactic {
mc = mc2;
}
}
break;
break;
}
case l_undef:
case l_undef:
// subgoal is unchanged.
break;
break;
}
TRACE("horn", g->display(tout););
SASSERT(g->is_well_sorted());
@ -314,20 +314,20 @@ class horn_tactic : public tactic {
}
}
void simplify(expr* q,
void simplify(expr* q,
goal_ref const& g,
goal_ref_buffer & result,
model_converter_ref & mc,
goal_ref_buffer & result,
model_converter_ref & mc,
proof_converter_ref & pc) {
expr_ref fml(m);
expr_ref fml(m);
func_decl* query_pred = to_app(q)->get_decl();
m_ctx.set_output_predicate(query_pred);
m_ctx.get_rules(); // flush adding rules.
apply_default_transformation(m_ctx);
if (m_ctx.xform_slice()) {
datalog::rule_transformer transformer(m_ctx);
datalog::mk_slice* slice = alloc(datalog::mk_slice, m_ctx);
@ -351,7 +351,7 @@ class horn_tactic : public tactic {
g->assert_expr(fml);
}
}
};
bool m_is_simplify;
@ -368,7 +368,7 @@ public:
tactic * translate(ast_manager & m) override {
return alloc(horn_tactic, m_is_simplify, m, m_params);
}
~horn_tactic() override {
dealloc(m_imp);
}
@ -378,16 +378,16 @@ public:
m_imp->updt_params(p);
}
void collect_param_descrs(param_descrs & r) override {
m_imp->collect_param_descrs(r);
}
void operator()(goal_ref const & in,
void operator()(goal_ref const & in,
goal_ref_buffer & result) override {
(*m_imp)(in, result);
}
void collect_statistics(statistics & st) const override {
m_imp->collect_statistics(st);
st.copy(m_stats);
@ -397,15 +397,15 @@ public:
m_stats.reset();
m_imp->reset_statistics();
}
void cleanup() override {
ast_manager & m = m_imp->m;
m_imp->collect_statistics(m_stats);
dealloc(m_imp);
m_imp = alloc(imp, m_is_simplify, m, m_params);
}
};
@ -416,4 +416,3 @@ tactic * mk_horn_tactic(ast_manager & m, params_ref const & p) {
tactic * mk_horn_simplify_tactic(ast_manager & m, params_ref const & p) {
return clean(alloc(horn_tactic, true, m, p));
}

20
src/muz/pdr/CMakeLists.txt
View file

@ -1,20 +0,0 @@
z3_add_component(pdr
SOURCES
pdr_closure.cpp
pdr_context.cpp
pdr_dl_interface.cpp
pdr_farkas_learner.cpp
pdr_generalizers.cpp
pdr_manager.cpp
pdr_prop_solver.cpp
pdr_reachable_cache.cpp
pdr_smt_context_manager.cpp
pdr_sym_mux.cpp
pdr_util.cpp
COMPONENT_DEPENDENCIES
arith_tactics
core_tactics
muz
smt_tactic
transforms
)

177
src/muz/pdr/pdr_closure.cpp
View file

@ -1,177 +0,0 @@
/*++
Copyright (c) 2013 Microsoft Corporation
Module Name:
pdr_closure.cpp
Abstract:
Utility functions for computing closures.
Author:
Nikolaj Bjorner (nbjorner) 2013-9-1.
Revision History:
--*/
#include "muz/pdr/pdr_closure.h"
#include "muz/pdr/pdr_context.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/ast_util.h"
namespace pdr {
expr_ref scaler::operator()(expr* e, expr* k, obj_map<func_decl, expr*>* translate) {
m_cache[0].reset();
m_cache[1].reset();
m_translate = translate;
m_k = k;
return scale(e, false);
}
expr_ref scaler::scale(expr* e, bool is_mul) {
expr* r;
if (m_cache[is_mul].find(e, r)) {
return expr_ref(r, m);
}
if (!is_app(e)) {
return expr_ref(e, m);
}
app* ap = to_app(e);
if (m_translate && m_translate->find(ap->get_decl(), r)) {
return expr_ref(r, m);
}
if (!is_mul && a.is_numeral(e)) {
return expr_ref(a.mk_mul(m_k, e), m);
}
expr_ref_vector args(m);
bool is_mul_rec = is_mul || a.is_mul(e);
for (unsigned i = 0; i < ap->get_num_args(); ++i) {
args.push_back(scale(ap->get_arg(i), is_mul_rec));
}
expr_ref result(m);
result = m.mk_app(ap->get_decl(), args.size(), args.c_ptr());
m_cache[is_mul].insert(e, result);
return result;
}
expr_ref scaler::undo_k(expr* e, expr* k) {
expr_safe_replace sub(m);
th_rewriter rw(m);
expr_ref result(e, m);
sub.insert(k, a.mk_numeral(rational(1), false));
sub(result);
rw(result);
return result;
}
closure::closure(pred_transformer& p, bool is_closure):
m(p.get_manager()), m_pt(p), a(m),
m_is_closure(is_closure), m_sigma(m), m_trail(m) {}
void closure::add_variables(unsigned num_vars, expr_ref_vector& fmls) {
manager& pm = m_pt.get_pdr_manager();
SASSERT(num_vars > 0);
while (m_vars.size() < num_vars) {
m_vars.resize(m_vars.size()+1);
m_sigma.push_back(m.mk_fresh_const("sigma", a.mk_real()));
}
unsigned sz = m_pt.sig_size();
for (unsigned i = 0; i < sz; ++i) {
expr* var;
ptr_vector<expr> vars;
func_decl* fn0 = m_pt.sig(i);
func_decl* fn1 = pm.o2n(fn0, 0);
sort* srt = fn0->get_range();
if (a.is_int_real(srt)) {
for (unsigned j = 0; j < num_vars; ++j) {
if (!m_vars[j].find(fn1, var)) {
var = m.mk_fresh_const(fn1->get_name().str().c_str(), srt);
m_trail.push_back(var);
m_vars[j].insert(fn1, var);
}
vars.push_back(var);
}
fmls.push_back(m.mk_eq(m.mk_const(fn1), a.mk_add(num_vars, vars.c_ptr())));
}
}
if (m_is_closure) {
for (unsigned i = 0; i < num_vars; ++i) {
fmls.push_back(a.mk_ge(m_sigma[i].get(), a.mk_numeral(rational(0), a.mk_real())));
}
}
else {
// is interior:
for (unsigned i = 0; i < num_vars; ++i) {
fmls.push_back(a.mk_gt(m_sigma[i].get(), a.mk_numeral(rational(0), a.mk_real())));
}
}
fmls.push_back(m.mk_eq(a.mk_numeral(rational(1), a.mk_real()), a.mk_add(num_vars, m_sigma.c_ptr())));
}
expr_ref closure::close_fml(expr* e) {
expr* e0, *e1, *e2;
expr_ref result(m);
if (a.is_lt(e, e1, e2)) {
result = a.mk_le(e1, e2);
}
else if (a.is_gt(e, e1, e2)) {
result = a.mk_ge(e1, e2);
}
else if (m.is_not(e, e0) && a.is_ge(e0, e1, e2)) {
result = a.mk_le(e1, e2);
}
else if (m.is_not(e, e0) && a.is_le(e0, e1, e2)) {
result = a.mk_ge(e1, e2);
}
else if (a.is_ge(e) || a.is_le(e) || m.is_eq(e) ||
(m.is_not(e, e0) && (a.is_gt(e0) || a.is_lt(e0)))) {
result = e;
}
else {
IF_VERBOSE(1, verbose_stream() << "Cannot close: " << mk_pp(e, m) << "\n";);
result = m.mk_true();
}
return result;
}
expr_ref closure::close_conjunction(expr* fml) {
expr_ref_vector fmls(m);
flatten_and(fml, fmls);
for (unsigned i = 0; i < fmls.size(); ++i) {
fmls[i] = close_fml(fmls[i].get());
}
return expr_ref(mk_and(fmls), m);
}
expr_ref closure::relax(unsigned i, expr* fml) {
scaler sc(m);
expr_ref result = sc(fml, m_sigma[i].get(), &m_vars[i]);
return close_conjunction(result);
}
expr_ref closure::operator()(expr_ref_vector const& As) {
if (As.empty()) {
return expr_ref(m.mk_false(), m);
}
if (As.size() == 1) {
return expr_ref(As[0], m);
}
expr_ref_vector fmls(m);
expr_ref B(m);
add_variables(As.size(), fmls);
for (unsigned i = 0; i < As.size(); ++i) {
fmls.push_back(relax(i, As[i]));
}
B = mk_and(fmls);
return B;
}
}

67
src/muz/pdr/pdr_closure.h
View file

@ -1,67 +0,0 @@
/*++
Copyright (c) 2013 Microsoft Corporation
Module Name:
pdr_closure.h
Abstract:
Utility functions for computing closures.
Author:
Nikolaj Bjorner (nbjorner) 2013-9-1.
Revision History:
--*/
#ifndef PDR_CLOSURE_H_
#define PDR_CLOSURE_H_
#include "ast/arith_decl_plugin.h"
namespace pdr {
// Arithmetic scaling functor.
// Variables are replaced using
// m_translate. Constants are replaced by
// multiplication with a variable 'k' (scale factor).
class scaler {
ast_manager& m;
arith_util a;
obj_map<expr, expr*> m_cache[2];
expr* m_k;
obj_map<func_decl, expr*>* m_translate;
public:
scaler(ast_manager& m): m(m), a(m), m_translate(nullptr) {}
expr_ref operator()(expr* e, expr* k, obj_map<func_decl, expr*>* translate = nullptr);
expr_ref undo_k(expr* e, expr* k);
private:
expr_ref scale(expr* e, bool is_mul);
};
class pred_transformer;
class closure {
ast_manager& m;
pred_transformer& m_pt;
arith_util a;
bool m_is_closure;
expr_ref_vector m_sigma;
expr_ref_vector m_trail;
vector<obj_map<func_decl, expr*> > m_vars;
expr_ref relax(unsigned i, expr* fml);
expr_ref close_conjunction(expr* fml);
expr_ref close_fml(expr* fml);
void add_variables(unsigned num_vars, expr_ref_vector& fmls);
public:
closure(pred_transformer& pt, bool is_closure);
expr_ref operator()(expr_ref_vector const& As);
};
}
#endif

2418
src/muz/pdr/pdr_context.cpp
View file

File diff suppressed because it is too large Load diff

448
src/muz/pdr/pdr_context.h
View file

@ -1,448 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_context.h
Abstract:
PDR for datalog
Author:
Nikolaj Bjorner (nbjorner) 2011-11-20.
Revision History:
--*/
#ifndef PDR_CONTEXT_H_
#define PDR_CONTEXT_H_
#ifdef _CYGWIN
#undef min
#undef max
#endif
#include <deque>
#include "muz/pdr/pdr_manager.h"
#include "muz/pdr/pdr_prop_solver.h"
#include "muz/pdr/pdr_reachable_cache.h"
#include "muz/base/fixedpoint_params.hpp"
namespace datalog {
class rule_set;
class context;
};
namespace pdr {
class pred_transformer;
class model_node;
class context;
typedef obj_map<datalog::rule const, app_ref_vector*> rule2inst;
typedef obj_map<func_decl, pred_transformer*> decl2rel;
//
// Predicate transformer state.
// A predicate transformer corresponds to the
// set of rules that have the same head predicates.
//
class pred_transformer {
struct stats {
unsigned m_num_propagations;
stats() { reset(); }
void reset() { memset(this, 0, sizeof(*this)); }
};
typedef obj_map<datalog::rule const, expr*> rule2expr;
typedef obj_map<datalog::rule const, ptr_vector<app> > rule2apps;
manager& pm; // pdr-manager
ast_manager& m; // manager
context& ctx;
func_decl_ref m_head; // predicate
func_decl_ref_vector m_sig; // signature
ptr_vector<pred_transformer> m_use; // places where 'this' is referenced.
ptr_vector<datalog::rule> m_rules; // rules used to derive transformer
prop_solver m_solver; // solver context
vector<expr_ref_vector> m_levels; // level formulas
expr_ref_vector m_invariants; // properties that are invariant.
obj_map<expr, unsigned> m_prop2level; // map property to level where it occurs.
obj_map<expr, datalog::rule const*> m_tag2rule; // map tag predicate to rule.
rule2expr m_rule2tag; // map rule to predicate tag.
rule2inst m_rule2inst; // map rules to instantiations of indices
rule2expr m_rule2transition; // map rules to transition
rule2apps m_rule2vars; // map rule to auxiliary variables
expr_ref m_transition; // transition relation.
expr_ref m_initial_state; // initial state.
reachable_cache m_reachable;
ptr_vector<func_decl> m_predicates;
stats m_stats;
void init_sig();
void ensure_level(unsigned level);
bool add_property1(expr * lemma, unsigned lvl); // add property 'p' to state at level lvl.
void add_child_property(pred_transformer& child, expr* lemma, unsigned lvl);
void mk_assumptions(func_decl* head, expr* fml, expr_ref_vector& result);
// Initialization
void init_rules(decl2rel const& pts, expr_ref& init, expr_ref& transition);
void init_rule(decl2rel const& pts, datalog::rule const& rule, expr_ref& init,
ptr_vector<datalog::rule const>& rules, expr_ref_vector& transition);
void init_atom(decl2rel const& pts, app * atom, app_ref_vector& var_reprs, expr_ref_vector& conj, unsigned tail_idx);
void simplify_formulas(tactic& tac, expr_ref_vector& fmls);
// Debugging
bool check_filled(app_ref_vector const& v) const;
void add_premises(decl2rel const& pts, unsigned lvl, datalog::rule& rule, expr_ref_vector& r);
public:
pred_transformer(context& ctx, manager& pm, func_decl* head);
~pred_transformer();
void add_rule(datalog::rule* r) { m_rules.push_back(r); }
void add_use(pred_transformer* pt) { if (!m_use.contains(pt)) m_use.insert(pt); }
void initialize(decl2rel const& pts);
func_decl* head() const { return m_head; }
ptr_vector<datalog::rule> const& rules() const { return m_rules; }
func_decl* sig(unsigned i) { init_sig(); return m_sig[i].get(); } // signature
func_decl* const* sig() { init_sig(); return m_sig.c_ptr(); }
unsigned sig_size() { init_sig(); return m_sig.size(); }
expr* transition() const { return m_transition; }
expr* initial_state() const { return m_initial_state; }
expr* rule2tag(datalog::rule const* r) { return m_rule2tag.find(r); }
unsigned get_num_levels() { return m_levels.size(); }
expr_ref get_cover_delta(func_decl* p_orig, int level);
void add_cover(unsigned level, expr* property);
context& get_context() { return ctx; }
std::ostream& display(std::ostream& strm) const;
void collect_statistics(statistics& st) const;
void reset_statistics();
bool is_reachable(expr* state);
void remove_predecessors(expr_ref_vector& literals);
void find_predecessors(datalog::rule const& r, ptr_vector<func_decl>& predicates) const;
datalog::rule const& find_rule(model_core const& model) const;
expr* get_transition(datalog::rule const& r) { return m_rule2transition.find(&r); }
ptr_vector<app>& get_aux_vars(datalog::rule const& r) { return m_rule2vars.find(&r); }
bool propagate_to_next_level(unsigned level);
void propagate_to_infinity(unsigned level);
void add_property(expr * lemma, unsigned lvl); // add property 'p' to state at level.
lbool is_reachable(model_node& n, expr_ref_vector* core, bool& uses_level);
bool is_invariant(unsigned level, expr* co_state, bool inductive, bool& assumes_level, expr_ref_vector* core = nullptr);
bool check_inductive(unsigned level, expr_ref_vector& state, bool& assumes_level);
expr_ref get_formulas(unsigned level, bool add_axioms);
void simplify_formulas();
expr_ref get_propagation_formula(decl2rel const& pts, unsigned level);
manager& get_pdr_manager() const { return pm; }
ast_manager& get_manager() const { return m; }
void add_premises(decl2rel const& pts, unsigned lvl, expr_ref_vector& r);
void close(expr* e);
app_ref_vector& get_inst(datalog::rule const* r) { return *m_rule2inst.find(r);}
void inherit_properties(pred_transformer& other);
void ground_free_vars(expr* e, app_ref_vector& vars, ptr_vector<app>& aux_vars);
prop_solver& get_solver() { return m_solver; }
prop_solver const& get_solver() const { return m_solver; }
void set_use_farkas(bool f) { get_solver().set_use_farkas(f); }
bool get_use_farkas() const { return get_solver().get_use_farkas(); }
class scoped_farkas {
bool m_old;
pred_transformer& m_p;
public:
scoped_farkas(pred_transformer& p, bool v): m_old(p.get_use_farkas()), m_p(p) {
p.set_use_farkas(v);
}
~scoped_farkas() { m_p.set_use_farkas(m_old); }
};
};
// structure for counter-example search.
class model_node {
model_node* m_parent;
model_node* m_next;
model_node* m_prev;
pred_transformer& m_pt;
expr_ref m_state;
model_ref m_model;
ptr_vector<model_node> m_children;
unsigned m_level;
unsigned m_orig_level;
unsigned m_depth;
bool m_closed;
datalog::rule const* m_rule;
public:
model_node(model_node* parent, expr_ref& state, pred_transformer& pt, unsigned level):
m_parent(parent), m_next(nullptr), m_prev(nullptr), m_pt(pt), m_state(state), m_model(nullptr),
m_level(level), m_orig_level(level), m_depth(0), m_closed(false), m_rule(nullptr) {
model_node* p = m_parent;
if (p) {
p->m_children.push_back(this);
SASSERT(p->m_level == level+1);
SASSERT(p->m_level > 0);
m_depth = p->m_depth+1;
if (p && p->is_closed()) {
p->set_open();
}
}
}
void set_model(model_ref& m) { m_model = m; }
unsigned level() const { return m_level; }
unsigned orig_level() const { return m_orig_level; }
unsigned depth() const { return m_depth; }
void increase_level() { ++m_level; }
expr_ref const& state() const { return m_state; }
ptr_vector<model_node> const& children() { return m_children; }
pred_transformer& pt() const { return m_pt; }
model_node* parent() const { return m_parent; }
model* get_model_ptr() const { return m_model.get(); }
model const& get_model() const { return *m_model; }
unsigned index() const;
bool is_closed() const { return m_closed; }
bool is_open() const { return !is_closed(); }
bool is_1closed() {
if (is_closed()) return true;
if (m_children.empty()) return false;
for (unsigned i = 0; i < m_children.size(); ++i) {
if (m_children[i]->is_open()) return false;
}
return true;
}
void check_pre_closed();
void set_closed();
void set_open();
void set_pre_closed() { TRACE("pdr", tout << state() << "\n";); m_closed = true; }
void reset() { m_children.reset(); }
void set_rule(datalog::rule const* r) { m_rule = r; }
datalog::rule* get_rule();
void mk_instantiate(datalog::rule_ref& r0, datalog::rule_ref& r1, expr_ref_vector& binding);
std::ostream& display(std::ostream& out, unsigned indent);
void dequeue(model_node*& root);
void enqueue(model_node* n);
model_node* next() const { return m_next; }
bool is_goal() const { return nullptr != next(); }
};
class model_search {
typedef ptr_vector<model_node> model_nodes;
bool m_bfs;
model_node* m_root;
model_node* m_goal;
vector<obj_map<expr, model_nodes > > m_cache;
obj_map<expr, model_nodes>& cache(model_node const& n);
void erase_children(model_node& n, bool backtrack);
void remove_node(model_node& n, bool backtrack);
void enqueue_leaf(model_node* n); // add leaf to priority queue.
void update_models();
void set_leaf(model_node& n); // Set node as leaf, remove children.
unsigned num_goals() const;
public:
model_search(bool bfs): m_bfs(bfs), m_root(nullptr), m_goal(nullptr) {}
~model_search();
void reset();
model_node* next();
void add_leaf(model_node& n); // add fresh node.
void set_root(model_node* n);
model_node& get_root() const { return *m_root; }
std::ostream& display(std::ostream& out) const;
expr_ref get_trace(context const& ctx);
proof_ref get_proof_trace(context const& ctx);
void backtrack_level(bool uses_level, model_node& n);
void remove_goal(model_node& n);
void well_formed();
};
struct model_exception { };
struct inductive_exception {};
// 'state' is unsatisfiable at 'level' with 'core'.
// Minimize or weaken core.
class core_generalizer {
protected:
context& m_ctx;
public:
typedef vector<std::pair<expr_ref_vector,bool> > cores;
core_generalizer(context& ctx): m_ctx(ctx) {}
virtual ~core_generalizer() {}
virtual void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) = 0;
virtual void operator()(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) {
new_cores.push_back(std::make_pair(core, uses_level));
if (!core.empty()) {
(*this)(n, new_cores.back().first, new_cores.back().second);
}
}
virtual void collect_statistics(statistics& st) const {}
virtual void reset_statistics() {}
};
class context {
struct stats {
unsigned m_num_nodes;
unsigned m_max_depth;
stats() { reset(); }
void reset() { memset(this, 0, sizeof(*this)); }
};
smt_params& m_fparams;
fixedpoint_params const& m_params;
ast_manager& m;
datalog::context* m_context;
manager m_pm;
decl2rel m_rels; // Map from relation predicate to fp-operator.
decl2rel m_rels_tmp;
func_decl_ref m_query_pred;
pred_transformer* m_query;
mutable model_search m_search;
lbool m_last_result;
unsigned m_inductive_lvl;
unsigned m_expanded_lvl;
ptr_vector<core_generalizer> m_core_generalizers;
stats m_stats;
model_converter_ref m_mc;
proof_converter_ref m_pc;
// Functions used by search.
void solve_impl();
bool check_reachability(unsigned level);
void propagate(unsigned max_prop_lvl);
void close_node(model_node& n);
void check_pre_closed(model_node& n);
void expand_node(model_node& n);
lbool expand_state(model_node& n, expr_ref_vector& cube, bool& uses_level);
void create_children(model_node& n);
expr_ref mk_sat_answer() const;
expr_ref mk_unsat_answer();
// Generate inductive property
void get_level_property(unsigned lvl, expr_ref_vector& res, vector<relation_info> & rs);
// Initialization
class classifier_proc;
void init_core_generalizers(datalog::rule_set& rules);
bool check_invariant(unsigned lvl);
bool check_invariant(unsigned lvl, func_decl* fn);
void checkpoint();
void init_rules(datalog::rule_set& rules, decl2rel& transformers);
void simplify_formulas();
void reset_core_generalizers();
void reset(decl2rel& rels);
void validate();
void validate_proof();
void validate_search();
void validate_model();
public:
/**
Initial values of predicates are stored in corresponding relations in dctx.
We check whether there is some reachable state of the relation checked_relation.
*/
context(
smt_params& fparams,
fixedpoint_params const& params,
ast_manager& m);
~context();
smt_params& get_fparams() const { return m_fparams; }
fixedpoint_params const& get_params() const { return m_params; }
ast_manager& get_manager() const { return m; }
manager& get_pdr_manager() { return m_pm; }
decl2rel const& get_pred_transformers() const { return m_rels; }
pred_transformer& get_pred_transformer(func_decl* p) const { return *m_rels.find(p); }
datalog::context& get_context() const { SASSERT(m_context); return *m_context; }
expr_ref get_answer();
bool is_dl() const { return m_fparams.m_arith_mode == AS_DIFF_LOGIC; }
bool is_utvpi() const { return m_fparams.m_arith_mode == AS_UTVPI; }
void collect_statistics(statistics& st) const;
void reset_statistics();
std::ostream& display(std::ostream& strm) const;
void display_certificate(std::ostream& strm);
lbool solve();
void reset(bool full = true);
void set_query(func_decl* q) { m_query_pred = q; }
void set_unsat() { m_last_result = l_false; }
void set_model_converter(model_converter_ref& mc) { m_mc = mc; }
model_converter_ref get_model_converter() { return m_mc; }
void set_proof_converter(proof_converter_ref& pc) { m_pc = pc; }
void update_rules(datalog::rule_set& rules);
void set_axioms(expr* axioms) { m_pm.set_background(axioms); }
unsigned get_num_levels(func_decl* p);
expr_ref get_cover_delta(int level, func_decl* p_orig, func_decl* p);
void add_cover(int level, func_decl* pred, expr* property);
model_ref get_model();
proof_ref get_proof() const;
model_node& get_root() const { return m_search.get_root(); }
};
};
#endif

225
src/muz/pdr/pdr_dl_interface.cpp
View file

@ -1,225 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_dl.cpp
Abstract:
SMT2 interface for the datalog PDR
Author:
Krystof Hoder (t-khoder) 2011-9-22.
Revision History:
--*/
#include "muz/base/dl_context.h"
#include "muz/transforms/dl_mk_coi_filter.h"
#include "muz/base/dl_rule.h"
#include "muz/base/dl_rule_transformer.h"
#include "muz/pdr/pdr_context.h"
#include "muz/pdr/pdr_dl_interface.h"
#include "muz/base/dl_rule_set.h"
#include "muz/transforms/dl_mk_slice.h"
#include "muz/transforms/dl_mk_unfold.h"
#include "muz/transforms/dl_mk_coalesce.h"
#include "muz/transforms/dl_transforms.h"
#include "ast/scoped_proof.h"
#include "model/model_smt2_pp.h"
using namespace pdr;
dl_interface::dl_interface(datalog::context& ctx) :
engine_base(ctx.get_manager(), "pdr"),
m_ctx(ctx),
m_pdr_rules(ctx),
m_old_rules(ctx),
m_context(nullptr),
m_refs(ctx.get_manager()) {
m_context = alloc(pdr::context, ctx.get_fparams(), ctx.get_params(), ctx.get_manager());
}
dl_interface::~dl_interface() {
dealloc(m_context);
}
//
// Check if the new rules are weaker so that we can
// re-use existing context.
//
void dl_interface::check_reset() {
datalog::rule_set const& new_rules = m_ctx.get_rules();
datalog::rule_ref_vector const& old_rules = m_old_rules.get_rules();
bool is_subsumed = !old_rules.empty();
for (unsigned i = 0; is_subsumed && i < new_rules.get_num_rules(); ++i) {
is_subsumed = false;
for (unsigned j = 0; !is_subsumed && j < old_rules.size(); ++j) {
if (m_ctx.check_subsumes(*old_rules[j], *new_rules.get_rule(i))) {
is_subsumed = true;
}
}
if (!is_subsumed) {
TRACE("pdr", new_rules.get_rule(i)->display(m_ctx, tout << "Fresh rule "););
m_context->reset();
}
}
m_old_rules.replace_rules(new_rules);
}
lbool dl_interface::query(expr * query) {
//we restore the initial state in the datalog context
m_ctx.ensure_opened();
m_refs.reset();
m_pred2slice.reset();
ast_manager& m = m_ctx.get_manager();
datalog::rule_manager& rm = m_ctx.get_rule_manager();
datalog::rule_set& rules0 = m_ctx.get_rules();
datalog::rule_set old_rules(rules0);
func_decl_ref query_pred(m);
rm.mk_query(query, rules0);
expr_ref bg_assertion = m_ctx.get_background_assertion();
check_reset();
TRACE("pdr",
if (!m.is_true(bg_assertion)) {
tout << "axioms:\n";
tout << mk_pp(bg_assertion, m) << "\n";
}
tout << "query: " << mk_pp(query, m) << "\n";
tout << "rules:\n";
m_ctx.display_rules(tout);
);
apply_default_transformation(m_ctx);
if (m_ctx.get_params().xform_slice()) {
datalog::rule_transformer transformer(m_ctx);
datalog::mk_slice* slice = alloc(datalog::mk_slice, m_ctx);
transformer.register_plugin(slice);
m_ctx.transform_rules(transformer);
// track sliced predicates.
obj_map<func_decl, func_decl*> const& preds = slice->get_predicates();
obj_map<func_decl, func_decl*>::iterator it = preds.begin();
obj_map<func_decl, func_decl*>::iterator end = preds.end();
for (; it != end; ++it) {
m_pred2slice.insert(it->m_key, it->m_value);
m_refs.push_back(it->m_key);
m_refs.push_back(it->m_value);
}
}
if (m_ctx.get_params().xform_unfold_rules() > 0) {
unsigned num_unfolds = m_ctx.get_params().xform_unfold_rules();
datalog::rule_transformer transf1(m_ctx), transf2(m_ctx);
transf1.register_plugin(alloc(datalog::mk_coalesce, m_ctx));
transf2.register_plugin(alloc(datalog::mk_unfold, m_ctx));
if (m_ctx.get_params().xform_coalesce_rules()) {
m_ctx.transform_rules(transf1);
}
while (num_unfolds > 0) {
m_ctx.transform_rules(transf2);
--num_unfolds;
}
}
const datalog::rule_set& rules = m_ctx.get_rules();
if (rules.get_output_predicates().empty()) {
m_context->set_unsat();
return l_false;
}
query_pred = rules.get_output_predicate();
TRACE("pdr",
tout << "rules:\n";
m_ctx.display_rules(tout);
m_ctx.display_smt2(0, 0, tout);
);
IF_VERBOSE(2, m_ctx.display_rules(verbose_stream()););
m_pdr_rules.replace_rules(rules);
m_pdr_rules.close();
m_ctx.record_transformed_rules();
m_ctx.reopen();
m_ctx.replace_rules(old_rules);
scoped_restore_proof _sc(m); // update_rules may overwrite the proof mode.
m_context->set_proof_converter(m_ctx.get_proof_converter());
m_context->set_model_converter(m_ctx.get_model_converter());
m_context->set_query(query_pred);
m_context->set_axioms(bg_assertion);
m_context->update_rules(m_pdr_rules);
if (m_pdr_rules.get_rules().empty()) {
m_context->set_unsat();
IF_VERBOSE(1, model_smt2_pp(verbose_stream(), m, *m_context->get_model(),0););
return l_false;
}
return m_context->solve();
}
expr_ref dl_interface::get_cover_delta(int level, func_decl* pred_orig) {
func_decl* pred = pred_orig;
m_pred2slice.find(pred_orig, pred);
SASSERT(pred);
return m_context->get_cover_delta(level, pred_orig, pred);
}
void dl_interface::add_cover(int level, func_decl* pred, expr* property) {
if (m_ctx.get_params().xform_slice()) {
throw default_exception("Covers are incompatible with slicing. Disable slicing before using covers");
}
m_context->add_cover(level, pred, property);
}
unsigned dl_interface::get_num_levels(func_decl* pred) {
m_pred2slice.find(pred, pred);
SASSERT(pred);
return m_context->get_num_levels(pred);
}
void dl_interface::collect_statistics(statistics& st) const {
m_context->collect_statistics(st);
}
void dl_interface::reset_statistics() {
m_context->reset_statistics();
}
void dl_interface::display_certificate(std::ostream& out) const {
m_context->display_certificate(out);
}
expr_ref dl_interface::get_answer() {
return m_context->get_answer();
}
void dl_interface::updt_params() {
dealloc(m_context);
m_context = alloc(pdr::context, m_ctx.get_fparams(), m_ctx.get_params(), m_ctx.get_manager());
}
model_ref dl_interface::get_model() {
return m_context->get_model();
}
proof_ref dl_interface::get_proof() {
return m_context->get_proof();
}

78
src/muz/pdr/pdr_dl_interface.h
View file

@ -1,78 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_dl_interface.h
Abstract:
SMT2 interface for the datalog PDR
Author:
Krystof Hoder (t-khoder) 2011-9-22.
Revision History:
--*/
#ifndef PDR_DL_INTERFACE_H_
#define PDR_DL_INTERFACE_H_
#include "util/lbool.h"
#include "muz/base/dl_rule.h"
#include "muz/base/dl_rule_set.h"
#include "muz/base/dl_util.h"
#include "muz/base/dl_engine_base.h"
#include "util/statistics.h"
namespace datalog {
class context;
}
namespace pdr {
class context;
class dl_interface : public datalog::engine_base {
datalog::context& m_ctx;
datalog::rule_set m_pdr_rules;
datalog::rule_set m_old_rules;
context* m_context;
obj_map<func_decl, func_decl*> m_pred2slice;
ast_ref_vector m_refs;
void check_reset();
public:
dl_interface(datalog::context& ctx);
~dl_interface() override;
lbool query(expr* query) override;
void display_certificate(std::ostream& out) const override;
void collect_statistics(statistics& st) const override;
void reset_statistics() override;
expr_ref get_answer() override;
unsigned get_num_levels(func_decl* pred) override;
expr_ref get_cover_delta(int level, func_decl* pred) override;
void add_cover(int level, func_decl* pred, expr* property) override;
void updt_params() override;
model_ref get_model() override;
proof_ref get_proof() override;
};
}
#endif

1012
src/muz/pdr/pdr_farkas_learner.cpp
View file

File diff suppressed because it is too large Load diff

128
src/muz/pdr/pdr_farkas_learner.h
View file

@ -1,128 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_farkas_learner.h
Abstract:
SMT2 interface for the datalog PDR
Author:
Krystof Hoder (t-khoder) 2011-11-1.
Revision History:
--*/
#ifndef PDR_FARKAS_LEARNER_H_
#define PDR_FARKAS_LEARNER_H_
#include "ast/arith_decl_plugin.h"
#include "ast/ast_translation.h"
#include "ast/bv_decl_plugin.h"
#include "smt/smt_kernel.h"
#include "ast/rewriter/bool_rewriter.h"
#include "muz/pdr/pdr_util.h"
#include "smt/params/smt_params.h"
#include "tactic/tactic.h"
namespace pdr {
class farkas_learner {
class farkas_collector;
class constant_replacer_cfg;
class equality_expander_cfg;
class constr;
typedef obj_hashtable<expr> expr_set;
smt_params m_proof_params;
ast_manager m_pr;
scoped_ptr<smt::kernel> m_ctx;
constr* m_constr;
//
// true: produce a combined constraint by applying Farkas coefficients.
// false: produce a conjunction of the negated literals from the theory lemmas.
//
bool m_combine_farkas_coefficients;
static smt_params get_proof_params(smt_params& orig_params);
//
// all ast objects passed to private functions have m_proof_mgs as their ast_manager
//
ast_translation p2o; /** Translate expression from inner ast_manager to outer one */
ast_translation o2p; /** Translate expression from outer ast_manager to inner one */
/** All ast opbjects here are in the m_proof_mgs */
void get_lemma_guesses_internal(proof * p, expr* A, expr * B, expr_ref_vector& lemmas);
bool farkas2lemma(proof * fstep, expr* A, expr * B, expr_ref& res);
void combine_constraints(unsigned cnt, app * const * constrs, rational const * coeffs, expr_ref& res);
bool try_ensure_lemma_in_language(expr_ref& lemma, expr* A, const func_decl_set& lang);
bool is_farkas_lemma(ast_manager& m, expr* e);
void get_asserted(proof* p, expr_set const& bs, ast_mark& b_closed, obj_hashtable<expr>& lemma_set, expr_ref_vector& lemmas);
bool is_pure_expr(func_decl_set const& symbs, expr* e) const;
static void test();
public:
farkas_learner(smt_params& params, ast_manager& m);
~farkas_learner();
/**
All ast objects have the ast_manager which was passed as
an argument to the constructor (i.e. m_outer_mgr)
B is a conjunction of literals.
A && B is unsat, equivalently A => ~B is valid
Find a weakened B' such that
A && B' is unsat and B' uses vocabulary (and constants) in common with A.
return lemmas to weaken B.
*/
bool get_lemma_guesses(expr * A, expr * B, expr_ref_vector& lemmas);
/**
Traverse a proof and retrieve lemmas using the vocabulary from bs.
*/
void get_lemmas(proof* root, expr_set const& bs, expr_ref_vector& lemmas);
/**
Traverse a proof and retrieve consequences of A that are used to establish ~B.
The assumption is that:
A => \/ ~consequences[i] and \/ ~consequences[i] => ~B
e.g., the second implication can be rewritten as:
B => /\ consequences[i]
*/
void get_consequences(proof* root, expr_set const& bs, expr_ref_vector& consequences);
/**
\brief Simplify lemmas using subsumption.
*/
void simplify_lemmas(expr_ref_vector& lemmas);
void collect_statistics(statistics& st) const;
};
}
#endif

777
src/muz/pdr/pdr_generalizers.cpp
View file

@ -1,777 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_generalizers.cpp
Abstract:
Generalizers of satisfiable states and unsat cores.
Author:
Nikolaj Bjorner (nbjorner) 2011-11-20.
Revision History:
--*/
#include "muz/pdr/pdr_context.h"
#include "muz/pdr/pdr_farkas_learner.h"
#include "muz/pdr/pdr_generalizers.h"
#include "ast/expr_abstract.h"
#include "ast/rewriter/var_subst.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "model/model_smt2_pp.h"
namespace pdr {
// ------------------------
// core_bool_inductive_generalizer
// main propositional induction generalizer.
// drop literals one by one from the core and check if the core is still inductive.
//
void core_bool_inductive_generalizer::operator()(model_node& n, expr_ref_vector& core, bool& uses_level) {
if (core.size() <= 1) {
return;
}
ast_manager& m = core.get_manager();
TRACE("pdr", for (unsigned i = 0; i < core.size(); ++i) { tout << mk_pp(core[i].get(), m) << "\n"; });
unsigned num_failures = 0, i = 0, old_core_size = core.size();
ptr_vector<expr> processed;
while (i < core.size() && 1 < core.size() && (!m_failure_limit || num_failures <= m_failure_limit)) {
expr_ref lit(m);
lit = core[i].get();
core[i] = m.mk_true();
if (n.pt().check_inductive(n.level(), core, uses_level)) {
num_failures = 0;
for (i = 0; i < core.size() && processed.contains(core[i].get()); ++i);
}
else {
core[i] = lit;
processed.push_back(lit);
++num_failures;
++i;
}
}
IF_VERBOSE(2, verbose_stream() << "old size: " << old_core_size << " new size: " << core.size() << "\n";);
TRACE("pdr", tout << "old size: " << old_core_size << " new size: " << core.size() << "\n";);
}
void core_multi_generalizer::operator()(model_node& n, expr_ref_vector& core, bool& uses_level) {
UNREACHABLE();
}
/**
\brief Find minimal cores.
Apply a simple heuristic: find a minimal core, then find minimal cores that exclude at least one
literal from each of the literals in the minimal cores.
*/
void core_multi_generalizer::operator()(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) {
ast_manager& m = core.get_manager();
expr_ref_vector old_core(m), core0(core);
bool uses_level1 = uses_level;
m_gen(n, core0, uses_level1);
new_cores.push_back(std::make_pair(core0, uses_level1));
obj_hashtable<expr> core_exprs, core1_exprs;
set_union(core_exprs, core0);
for (unsigned i = 0; i < old_core.size(); ++i) {
expr* lit = old_core[i].get();
if (core_exprs.contains(lit)) {
expr_ref_vector core1(old_core);
core1[i] = core1.back();
core1.pop_back();
uses_level1 = uses_level;
m_gen(n, core1, uses_level1);
SASSERT(core1.size() <= old_core.size());
if (core1.size() < old_core.size()) {
new_cores.push_back(std::make_pair(core1, uses_level1));
core1_exprs.reset();
set_union(core1_exprs, core1);
set_intersection(core_exprs, core1_exprs);
}
}
}
}
// ------------------------
// core_farkas_generalizer
//
// for each disjunct of core:
// weaken predecessor.
//
core_farkas_generalizer::core_farkas_generalizer(context& ctx, ast_manager& m, smt_params& p):
core_generalizer(ctx),
m_farkas_learner(p, m)
{}
void core_farkas_generalizer::operator()(model_node& n, expr_ref_vector& core, bool& uses_level) {
ast_manager& m = n.pt().get_manager();
if (core.empty()) return;
expr_ref A(m), B(mk_and(core)), C(m);
expr_ref_vector Bs(m);
flatten_or(B, Bs);
A = n.pt().get_propagation_formula(m_ctx.get_pred_transformers(), n.level());
bool change = false;
for (unsigned i = 0; i < Bs.size(); ++i) {
expr_ref_vector lemmas(m);
C = Bs[i].get();
if (m_farkas_learner.get_lemma_guesses(A, B, lemmas)) {
TRACE("pdr",
tout << "Old core:\n" << mk_pp(B, m) << "\n";
tout << "New core:\n" << mk_and(lemmas) << "\n";);
Bs[i] = mk_and(lemmas);
change = true;
}
}
if (change) {
C = mk_or(Bs);
TRACE("pdr", tout << "prop:\n" << mk_pp(A,m) << "\ngen:" << mk_pp(B, m) << "\nto: " << mk_pp(C, m) << "\n";);
core.reset();
flatten_and(C, core);
uses_level = true;
}
}
void core_farkas_generalizer::collect_statistics(statistics& st) const {
m_farkas_learner.collect_statistics(st);
}
core_convex_hull_generalizer::core_convex_hull_generalizer(context& ctx, bool is_closure):
core_generalizer(ctx),
m(ctx.get_manager()),
m_is_closure(is_closure) {
}
void core_convex_hull_generalizer::operator()(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) {
// method3(n, core, uses_level, new_cores);
method1(n, core, uses_level, new_cores);
}
void core_convex_hull_generalizer::operator()(model_node& n, expr_ref_vector& core, bool& uses_level) {
UNREACHABLE();
}
// use the entire region as starting point for generalization.
//
// Constraints:
// add_variables: y = y1 + y2
// core: Ay <= b -> conv1: A*y1 <= b*sigma1
// sigma1 > 0
// sigma2 > 0
// 1 = sigma1 + sigma2
// A'y <= b' -> conv2: A'*y2 <= b'*sigma2
//
// If Constraints & Transition(y0, y) is unsat, then
// update with new core.
//
void core_convex_hull_generalizer::method1(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) {
expr_ref_vector conv2(m), fmls(m), fml1_2(m);
bool change = false;
if (core.empty()) {
new_cores.push_back(std::make_pair(core, uses_level));
return;
}
closure cl(n.pt(), m_is_closure);
expr_ref fml1 = mk_and(core);
expr_ref fml2 = n.pt().get_formulas(n.level(), false);
fml1_2.push_back(fml1);
fml1_2.push_back(nullptr);
flatten_and(fml2, fmls);
for (unsigned i = 0; i < fmls.size(); ++i) {
fml2 = m.mk_not(fmls[i].get());
fml1_2[1] = fml2;
expr_ref state = cl(fml1_2);
TRACE("pdr",
tout << "Check states:\n" << mk_pp(state, m) << "\n";
tout << "Old states:\n" << mk_pp(fml2, m) << "\n";
);
model_node nd(nullptr, state, n.pt(), n.level());
pred_transformer::scoped_farkas sf(n.pt(), true);
bool uses_level1 = uses_level;
if (l_false == n.pt().is_reachable(nd, &conv2, uses_level1)) {
new_cores.push_back(std::make_pair(conv2, uses_level1));
change = true;
expr_ref state1 = mk_and(conv2);
TRACE("pdr",
tout << mk_pp(state, m) << "\n";
tout << "Generalized to:\n" << mk_pp(state1, m) << "\n";);
IF_VERBOSE(0,
verbose_stream() << mk_pp(state, m) << "\n";
verbose_stream() << "Generalized to:\n" << mk_pp(state1, m) << "\n";);
}
}
if (!m_is_closure || !change) {
new_cores.push_back(std::make_pair(core, uses_level));
}
}
/*
Extract the lemmas from the transition relation that were used to establish unsatisfiability.
Take convex closures of conbinations of these lemmas.
*/
void core_convex_hull_generalizer::method3(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) {
TRACE("dl", tout << "method: generalize consequences of F(R)\n";
for (unsigned i = 0; i < core.size(); ++i) {
tout << "B:" << mk_pp(core[i], m) << "\n";
});
bool uses_level1;
expr_ref_vector core1(m);
core1.append(core);
expr_ref_vector consequences(m);
{
n.pt().get_solver().set_consequences(&consequences);
pred_transformer::scoped_farkas sf (n.pt(), true);
VERIFY(l_false == n.pt().is_reachable(n, &core1, uses_level1));
n.pt().get_solver().set_consequences(nullptr);
}
IF_VERBOSE(0,
verbose_stream() << "Consequences: " << consequences.size() << "\n";
for (unsigned i = 0; i < consequences.size(); ++i) {
verbose_stream() << mk_pp(consequences[i].get(), m) << "\n";
}
verbose_stream() << "core: " << core1.size() << "\n";
for (unsigned i = 0; i < core1.size(); ++i) {
verbose_stream() << mk_pp(core1[i].get(), m) << "\n";
});
expr_ref tmp(m);
// Check that F(R) => \/ consequences
{
expr_ref_vector cstate(m);
for (unsigned i = 0; i < consequences.size(); ++i) {
cstate.push_back(m.mk_not(consequences[i].get()));
}
tmp = m.mk_and(cstate.size(), cstate.c_ptr());
model_node nd(nullptr, tmp, n.pt(), n.level());
pred_transformer::scoped_farkas sf (n.pt(), false);
VERIFY(l_false == n.pt().is_reachable(nd, &core1, uses_level1));
}
// Create disjunction.
tmp = m.mk_and(core.size(), core.c_ptr());
// Check that \/ consequences => not (core)
if (!is_unsat(consequences, tmp)) {
IF_VERBOSE(0, verbose_stream() << "Consequences don't contradict the core\n";);
return;
}
IF_VERBOSE(0, verbose_stream() << "Consequences contradict core\n";);
if (!strengthen_consequences(n, consequences, tmp)) {
return;
}
IF_VERBOSE(0, verbose_stream() << "consequences strengthened\n";);
// Use the resulting formula to find Farkas lemmas from core.
}
bool core_convex_hull_generalizer::strengthen_consequences(model_node& n, expr_ref_vector& As, expr* B) {
expr_ref A(m), tmp(m), convA(m);
unsigned sz = As.size();
closure cl(n.pt(), m_is_closure);
for (unsigned i = 0; i < As.size(); ++i) {
expr_ref_vector Hs(m);
Hs.push_back(As[i].get());
for (unsigned j = i + 1; j < As.size(); ++j) {
Hs.push_back(As[j].get());
bool unsat = false;
A = cl(Hs);
tmp = As[i].get();
As[i] = A;
unsat = is_unsat(As, B);
As[i] = tmp;
if (unsat) {
IF_VERBOSE(0, verbose_stream() << "New convex: " << mk_pp(convA, m) << "\n";);
convA = A;
As[j] = As.back();
As.pop_back();
--j;
}
else {
Hs.pop_back();
}
}
if (Hs.size() > 1) {
As[i] = convA;
}
}
return sz > As.size();
}
bool core_convex_hull_generalizer::is_unsat(expr_ref_vector const& As, expr* B) {
smt::kernel ctx(m, m_ctx.get_fparams(), m_ctx.get_params().p);
expr_ref disj(m);
disj = m.mk_or(As.size(), As.c_ptr());
ctx.assert_expr(disj);
ctx.assert_expr(B);
std::cout << "Checking\n" << mk_pp(disj, m) << "\n" << mk_pp(B, m) << "\n";
return l_false == ctx.check();
}
// ---------------------------------
// core_arith_inductive_generalizer
// NB. this is trying out some ideas for generalization in
// an ad hoc specialized way. arith_inductive_generalizer should
// not be used by default. It is a place-holder for a general purpose
// extrapolator of a lattice basis.
core_arith_inductive_generalizer::core_arith_inductive_generalizer(context& ctx):
core_generalizer(ctx),
m(ctx.get_manager()),
a(m),
m_refs(m) {}
void core_arith_inductive_generalizer::operator()(model_node& n, expr_ref_vector& core, bool& uses_level) {
if (core.size() <= 1) {
return;
}
reset();
expr_ref e(m), t1(m), t2(m), t3(m);
rational r;
TRACE("pdr", for (unsigned i = 0; i < core.size(); ++i) { tout << mk_pp(core[i].get(), m) << "\n"; });
svector<eq> eqs;
get_eqs(core, eqs);
if (eqs.empty()) {
return;
}
expr_ref_vector new_core(m);
new_core.append(core);
for (unsigned eq = 0; eq < eqs.size(); ++eq) {
rational r = eqs[eq].m_value;
expr* x = eqs[eq].m_term;
unsigned k = eqs[eq].m_i;
unsigned l = eqs[eq].m_j;
new_core[l] = m.mk_true();
new_core[k] = m.mk_true();
for (unsigned i = 0; i < new_core.size(); ++i) {
if (substitute_alias(r, x, new_core[i].get(), e)) {
new_core[i] = e;
}
}
if (abs(r) >= rational(2) && a.is_int(x)) {
new_core[k] = m.mk_eq(a.mk_mod(x, a.mk_numeral(rational(2), true)), a.mk_numeral(rational(0), true));
new_core[l] = a.mk_le(x, a.mk_numeral(rational(0), true));
}
}
bool inductive = n.pt().check_inductive(n.level(), new_core, uses_level);
IF_VERBOSE(1,
verbose_stream() << (inductive?"":"non") << "inductive\n";
verbose_stream() << "old\n";
for (unsigned j = 0; j < core.size(); ++j) {
verbose_stream() << mk_pp(core[j].get(), m) << "\n";
}
verbose_stream() << "new\n";
for (unsigned j = 0; j < new_core.size(); ++j) {
verbose_stream() << mk_pp(new_core[j].get(), m) << "\n";
});
if (inductive) {
core.reset();
core.append(new_core);
}
}
void core_arith_inductive_generalizer::insert_bound(bool is_lower, expr* x, rational const& r, unsigned i) {
if (r.is_neg()) {
expr_ref e(m);
e = a.mk_uminus(x);
m_refs.push_back(e);
x = e;
is_lower = !is_lower;
}
vector<term_loc_t> bound;
bound.push_back(std::make_pair(x, i));
if (is_lower) {
m_lb.insert(abs(r), bound);
}
else {
m_ub.insert(abs(r), bound);
}
}
void core_arith_inductive_generalizer::reset() {
m_refs.reset();
m_lb.reset();
m_ub.reset();
}
void core_arith_inductive_generalizer::get_eqs(expr_ref_vector const& core, svector<eq>& eqs) {
expr* e1, *x, *y;
expr_ref e(m);
rational r;
for (unsigned i = 0; i < core.size(); ++i) {
e = core[i];
if (m.is_not(e, e1) && a.is_le(e1, x, y) && a.is_numeral(y, r) && a.is_int(x)) {
// not (<= x r) <=> x >= r + 1
insert_bound(true, x, r + rational(1), i);
}
else if (m.is_not(e, e1) && a.is_ge(e1, x, y) && a.is_numeral(y, r) && a.is_int(x)) {
// not (>= x r) <=> x <= r - 1
insert_bound(false, x, r - rational(1), i);
}
else if (a.is_le(e, x, y) && a.is_numeral(y, r)) {
insert_bound(false, x, r, i);
}
else if (a.is_ge(e, x, y) && a.is_numeral(y, r)) {
insert_bound(true, x, r, i);
}
}
bounds_t::iterator it = m_lb.begin(), end = m_lb.end();
for (; it != end; ++it) {
rational r = it->m_key;
vector<term_loc_t> & terms1 = it->m_value;
vector<term_loc_t> terms2;
if (r >= rational(2) && m_ub.find(r, terms2)) {
for (unsigned i = 0; i < terms1.size(); ++i) {
bool done = false;
for (unsigned j = 0; !done && j < terms2.size(); ++j) {
expr* t1 = terms1[i].first;
expr* t2 = terms2[j].first;
if (t1 == t2) {
eqs.push_back(eq(t1, r, terms1[i].second, terms2[j].second));
done = true;
}
else {
e = m.mk_eq(t1, t2);
th_rewriter rw(m);
rw(e);
if (m.is_true(e)) {
eqs.push_back(eq(t1, r, terms1[i].second, terms2[j].second));
done = true;
}
}
}
}
}
}
}
bool core_arith_inductive_generalizer::substitute_alias(rational const& r, expr* x, expr* e, expr_ref& result) {
rational r2;
expr* y, *z, *e1;
if (m.is_not(e, e1) && substitute_alias(r, x, e1, result)) {
result = m.mk_not(result);
return true;
}
if (a.is_le(e, y, z) && a.is_numeral(z, r2)) {
if (r == r2) {
result = a.mk_le(y, x);
return true;
}
if (r == r2 + rational(1)) {
result = a.mk_lt(y, x);
return true;
}
if (r == r2 - rational(1)) {
result = a.mk_le(y, a.mk_sub(x, a.mk_numeral(rational(1), a.is_int(x))));
return true;
}
}
if (a.is_ge(e, y, z) && a.is_numeral(z, r2)) {
if (r == r2) {
result = a.mk_ge(y, x);
return true;
}
if (r2 == r + rational(1)) {
result = a.mk_gt(y, x);
return true;
}
if (r2 == r - rational(1)) {
result = a.mk_ge(y, a.mk_sub(x, a.mk_numeral(rational(1), a.is_int(x))));
return true;
}
}
return false;
}
//
// < F, phi, i + 1>
// |
// < G, psi, i >
//
// where:
//
// p(x) <- F(x,y,p,q)
// q(x) <- G(x,y)
//
// Hyp:
// Q_k(x) => phi(x) j <= k <= i
// Q_k(x) => R_k(x) j <= k <= i + 1
// Q_k(x) <=> Trans(Q_{k-1}) j < k <= i + 1
// Conclusion:
// Q_{i+1}(x) => phi(x)
//
class core_induction_generalizer::imp {
context& m_ctx;
manager& pm;
ast_manager& m;
//
// Create predicate Q_level
//
func_decl_ref mk_pred(unsigned level, func_decl* f) {
func_decl_ref result(m);
std::ostringstream name;
name << f->get_name() << "_" << level;
symbol sname(name.str().c_str());
result = m.mk_func_decl(sname, f->get_arity(), f->get_domain(), f->get_range());
return result;
}
//
// Create formula exists y . z . F[Q_{level-1}, x, y, z]
//
expr_ref mk_transition_rule(
expr_ref_vector const& reps,
unsigned level,
datalog::rule const& rule)
{
expr_ref_vector conj(m), sub(m);
expr_ref result(m);
svector<symbol> names;
unsigned ut_size = rule.get_uninterpreted_tail_size();
unsigned t_size = rule.get_tail_size();
if (0 == level && 0 < ut_size) {
result = m.mk_false();
return result;
}
app* atom = rule.get_head();
SASSERT(atom->get_num_args() == reps.size());
for (unsigned i = 0; i < reps.size(); ++i) {
expr* arg = atom->get_arg(i);
if (is_var(arg)) {
unsigned idx = to_var(arg)->get_idx();
if (idx >= sub.size()) sub.resize(idx+1);
if (sub[idx].get()) {
conj.push_back(m.mk_eq(sub[idx].get(), reps[i]));
}
else {
sub[idx] = reps[i];
}
}
else {
conj.push_back(m.mk_eq(arg, reps[i]));
}
}
for (unsigned i = 0; 0 < level && i < ut_size; i++) {
app* atom = rule.get_tail(i);
func_decl* head = atom->get_decl();
func_decl_ref fn = mk_pred(level-1, head);
conj.push_back(m.mk_app(fn, atom->get_num_args(), atom->get_args()));
}
for (unsigned i = ut_size; i < t_size; i++) {
conj.push_back(rule.get_tail(i));
}
result = mk_and(conj);
if (!sub.empty()) {
expr_ref tmp = result;
var_subst(m, false)(tmp, sub.size(), sub.c_ptr(), result);
}
expr_free_vars fv;
fv(result);
fv.set_default_sort(m.mk_bool_sort());
for (unsigned i = 0; i < fv.size(); ++i) {
names.push_back(symbol(fv.size() - i - 1));
}
if (!fv.empty()) {
fv.reverse();
result = m.mk_exists(fv.size(), fv.c_ptr(), names.c_ptr(), result);
}
return result;
}
expr_ref bind_head(expr_ref_vector const& reps, expr* fml) {
expr_ref result(m);
expr_abstract(m, 0, reps.size(), reps.c_ptr(), fml, result);
ptr_vector<sort> sorts;
svector<symbol> names;
unsigned sz = reps.size();
for (unsigned i = 0; i < sz; ++i) {
sorts.push_back(m.get_sort(reps[sz-i-1]));
names.push_back(symbol(sz-i-1));
}
if (sz > 0) {
result = m.mk_forall(sorts.size(), sorts.c_ptr(), names.c_ptr(), result);
}
return result;
}
expr_ref_vector mk_reps(pred_transformer& pt) {
expr_ref_vector reps(m);
expr_ref rep(m);
for (unsigned i = 0; i < pt.head()->get_arity(); ++i) {
rep = m.mk_const(pm.o2n(pt.sig(i), 0));
reps.push_back(rep);
}
return reps;
}
//
// extract transition axiom:
//
// forall x . p_lvl(x) <=> exists y z . F[p_{lvl-1}(y), q_{lvl-1}(z), x]
//
expr_ref mk_transition_axiom(pred_transformer& pt, unsigned level) {
expr_ref fml(m.mk_false(), m), tr(m);
expr_ref_vector reps = mk_reps(pt);
ptr_vector<datalog::rule> const& rules = pt.rules();
for (unsigned i = 0; i < rules.size(); ++i) {
tr = mk_transition_rule(reps, level, *rules[i]);
fml = (i == 0)?tr.get():m.mk_or(fml, tr);
}
func_decl_ref fn = mk_pred(level, pt.head());
fml = m.mk_iff(m.mk_app(fn, reps.size(), reps.c_ptr()), fml);
fml = bind_head(reps, fml);
return fml;
}
//
// Create implication:
// Q_level(x) => phi(x)
//
expr_ref mk_predicate_property(unsigned level, pred_transformer& pt, expr* phi) {
expr_ref_vector reps = mk_reps(pt);
func_decl_ref fn = mk_pred(level, pt.head());
expr_ref fml(m);
fml = m.mk_implies(m.mk_app(fn, reps.size(), reps.c_ptr()), phi);
fml = bind_head(reps, fml);
return fml;
}
public:
imp(context& ctx): m_ctx(ctx), pm(ctx.get_pdr_manager()), m(ctx.get_manager()) {}
//
// not exists y . F(x,y)
//
expr_ref mk_blocked_transition(pred_transformer& pt, unsigned level) {
SASSERT(level > 0);
expr_ref fml(m.mk_true(), m);
expr_ref_vector reps = mk_reps(pt), fmls(m);
ptr_vector<datalog::rule> const& rules = pt.rules();
for (unsigned i = 0; i < rules.size(); ++i) {
fmls.push_back(m.mk_not(mk_transition_rule(reps, level, *rules[i])));
}
fml = mk_and(fmls);
TRACE("pdr", tout << mk_pp(fml, m) << "\n";);
return fml;
}
expr_ref mk_induction_goal(pred_transformer& pt, unsigned level, unsigned depth) {
SASSERT(level >= depth);
expr_ref_vector conjs(m);
ptr_vector<pred_transformer> pts;
unsigned_vector levels;
// negated goal
expr_ref phi = mk_blocked_transition(pt, level);
conjs.push_back(m.mk_not(mk_predicate_property(level, pt, phi)));
pts.push_back(&pt);
levels.push_back(level);
// Add I.H.
for (unsigned lvl = level-depth; lvl < level; ++lvl) {
if (lvl > 0) {
expr_ref psi = mk_blocked_transition(pt, lvl);
conjs.push_back(mk_predicate_property(lvl, pt, psi));
pts.push_back(&pt);
levels.push_back(lvl);
}
}
// Transitions:
for (unsigned qhead = 0; qhead < pts.size(); ++qhead) {
pred_transformer& qt = *pts[qhead];
unsigned lvl = levels[qhead];
// Add transition definition and properties at level.
conjs.push_back(mk_transition_axiom(qt, lvl));
conjs.push_back(mk_predicate_property(lvl, qt, qt.get_formulas(lvl, true)));
// Enqueue additional hypotheses
ptr_vector<datalog::rule> const& rules = qt.rules();
if (lvl + depth < level || lvl == 0) {
continue;
}
for (unsigned i = 0; i < rules.size(); ++i) {
datalog::rule& r = *rules[i];
unsigned ut_size = r.get_uninterpreted_tail_size();
for (unsigned j = 0; j < ut_size; ++j) {
func_decl* f = r.get_tail(j)->get_decl();
pred_transformer* rt = m_ctx.get_pred_transformers().find(f);
bool found = false;
for (unsigned k = 0; !found && k < levels.size(); ++k) {
found = (rt == pts[k] && levels[k] + 1 == lvl);
}
if (!found) {
levels.push_back(lvl-1);
pts.push_back(rt);
}
}
}
}
expr_ref result = mk_and(conjs);
TRACE("pdr", tout << mk_pp(result, m) << "\n";);
return result;
}
};
//
// Instantiate Peano induction schema.
//
void core_induction_generalizer::operator()(model_node& n, expr_ref_vector& core, bool& uses_level) {
model_node* p = n.parent();
if (p == nullptr) {
return;
}
unsigned depth = 2;
imp imp(m_ctx);
ast_manager& m = core.get_manager();
expr_ref goal = imp.mk_induction_goal(p->pt(), p->level(), depth);
smt::kernel ctx(m, m_ctx.get_fparams(), m_ctx.get_params().p);
ctx.assert_expr(goal);
lbool r = ctx.check();
TRACE("pdr", tout << r << "\n";
for (unsigned i = 0; i < core.size(); ++i) {
tout << mk_pp(core[i].get(), m) << "\n";
});
if (r == l_false) {
core.reset();
expr_ref phi = imp.mk_blocked_transition(p->pt(), p->level());
core.push_back(m.mk_not(phi));
uses_level = true;
}
}
};

110
src/muz/pdr/pdr_generalizers.h
View file

@ -1,110 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_generalizers.h
Abstract:
Generalizer plugins.
Author:
Nikolaj Bjorner (nbjorner) 2011-11-22.
Revision History:
--*/
#ifndef PDR_GENERALIZERS_H_
#define PDR_GENERALIZERS_H_
#include "muz/pdr/pdr_context.h"
#include "muz/pdr/pdr_closure.h"
#include "ast/arith_decl_plugin.h"
namespace pdr {
class core_bool_inductive_generalizer : public core_generalizer {
unsigned m_failure_limit;
public:
core_bool_inductive_generalizer(context& ctx, unsigned failure_limit) : core_generalizer(ctx), m_failure_limit(failure_limit) {}
~core_bool_inductive_generalizer() override {}
void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) override;
};
template <typename T>
class r_map : public map<rational, T, rational::hash_proc, rational::eq_proc> {
};
class core_arith_inductive_generalizer : public core_generalizer {
typedef std::pair<expr*, unsigned> term_loc_t;
typedef r_map<vector<term_loc_t> > bounds_t;
ast_manager& m;
arith_util a;
expr_ref_vector m_refs;
bounds_t m_lb;
bounds_t m_ub;
struct eq {
expr* m_term;
rational m_value;
unsigned m_i;
unsigned m_j;
eq(expr* t, rational const& r, unsigned i, unsigned j): m_term(t), m_value(r), m_i(i), m_j(j) {}
};
void reset();
void insert_bound(bool is_lower, expr* x, rational const& r, unsigned i);
void get_eqs(expr_ref_vector const& core, svector<eq>& eqs);
bool substitute_alias(rational const&r, expr* x, expr* e, expr_ref& result);
public:
core_arith_inductive_generalizer(context& ctx);
~core_arith_inductive_generalizer() override {}
void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) override;
};
class core_farkas_generalizer : public core_generalizer {
farkas_learner m_farkas_learner;
public:
core_farkas_generalizer(context& ctx, ast_manager& m, smt_params& p);
~core_farkas_generalizer() override {}
void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) override;
void collect_statistics(statistics& st) const override;
};
class core_convex_hull_generalizer : public core_generalizer {
ast_manager& m;
obj_map<expr, expr*> m_models;
bool m_is_closure;
void method1(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores);
void method3(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores);
bool strengthen_consequences(model_node& n, expr_ref_vector& As, expr* B);
bool is_unsat(expr_ref_vector const& As, expr* B);
public:
core_convex_hull_generalizer(context& ctx, bool is_closure);
~core_convex_hull_generalizer() override {}
void operator()(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) override;
void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) override;
};
class core_multi_generalizer : public core_generalizer {
core_bool_inductive_generalizer m_gen;
public:
core_multi_generalizer(context& ctx, unsigned max_failures): core_generalizer(ctx), m_gen(ctx, max_failures) {}
~core_multi_generalizer() override {}
void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) override;
void operator()(model_node& n, expr_ref_vector const& core, bool uses_level, cores& new_cores) override;
};
class core_induction_generalizer : public core_generalizer {
class imp;
public:
core_induction_generalizer(context& ctx): core_generalizer(ctx) {}
~core_induction_generalizer() override {}
void operator()(model_node& n, expr_ref_vector& core, bool& uses_level) override;
};
};
#endif

321
src/muz/pdr/pdr_manager.cpp
View file

@ -1,321 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_manager.cpp
Abstract:
A manager class for PDR, taking care of creating of AST
objects and conversions between them.
Author:
Krystof Hoder (t-khoder) 2011-8-25.
Revision History:
--*/
#include <sstream>
#include "muz/pdr/pdr_manager.h"
#include "ast/ast_smt2_pp.h"
#include "ast/for_each_expr.h"
#include "ast/has_free_vars.h"
#include "ast/rewriter/expr_replacer.h"
#include "ast/expr_abstract.h"
#include "model/model2expr.h"
#include "model/model_smt2_pp.h"
#include "tactic/model_converter.h"
namespace pdr {
class collect_decls_proc {
func_decl_set& m_bound_decls;
func_decl_set& m_aux_decls;
public:
collect_decls_proc(func_decl_set& bound_decls, func_decl_set& aux_decls):
m_bound_decls(bound_decls),
m_aux_decls(aux_decls) {
}
void operator()(app* a) {
if (a->get_family_id() == null_family_id) {
func_decl* f = a->get_decl();
if (!m_bound_decls.contains(f)) {
m_aux_decls.insert(f);
}
}
}
void operator()(var* v) {}
void operator()(quantifier* q) {}
};
typedef hashtable<symbol, symbol_hash_proc, symbol_eq_proc> symbol_set;
expr_ref inductive_property::fixup_clause(expr* fml) const {
expr_ref_vector disjs(m);
flatten_or(fml, disjs);
expr_ref result(m);
bool_rewriter(m).mk_or(disjs.size(), disjs.c_ptr(), result);
return result;
}
expr_ref inductive_property::fixup_clauses(expr* fml) const {
expr_ref_vector conjs(m);
expr_ref result(m);
flatten_and(fml, conjs);
for (unsigned i = 0; i < conjs.size(); ++i) {
conjs[i] = fixup_clause(conjs[i].get());
}
bool_rewriter(m).mk_and(conjs.size(), conjs.c_ptr(), result);
return result;
}
std::string inductive_property::to_string() const {
std::stringstream stm;
model_ref md;
expr_ref result(m);
to_model(md);
model_smt2_pp(stm, m, *md.get(), 0);
return stm.str();
}
void inductive_property::to_model(model_ref& md) const {
md = alloc(model, m);
vector<relation_info> const& rs = m_relation_info;
expr_ref_vector conjs(m);
for (unsigned i = 0; i < rs.size(); ++i) {
relation_info ri(rs[i]);
func_decl * pred = ri.m_pred;
expr_ref prop = fixup_clauses(ri.m_body);
func_decl_ref_vector const& sig = ri.m_vars;
expr_ref q(m);
expr_ref_vector sig_vars(m);
for (unsigned j = 0; j < sig.size(); ++j) {
sig_vars.push_back(m.mk_const(sig[sig.size()-j-1]));
}
expr_abstract(m, 0, sig_vars.size(), sig_vars.c_ptr(), prop, q);
if (sig.empty()) {
md->register_decl(pred, q);
}
else {
func_interp* fi = alloc(func_interp, m, sig.size());
fi->set_else(q);
md->register_decl(pred, fi);
}
}
TRACE("pdr", model_smt2_pp(tout, m, *md, 0););
apply(const_cast<model_converter_ref&>(m_mc), md);
}
expr_ref inductive_property::to_expr() const {
model_ref md;
expr_ref result(m);
to_model(md);
model2expr(md, result);
return result;
}
void inductive_property::display(datalog::rule_manager& rm, ptr_vector<datalog::rule> const& rules, std::ostream& out) const {
func_decl_set bound_decls, aux_decls;
collect_decls_proc collect_decls(bound_decls, aux_decls);
for (unsigned i = 0; i < m_relation_info.size(); ++i) {
bound_decls.insert(m_relation_info[i].m_pred);
func_decl_ref_vector const& sig = m_relation_info[i].m_vars;
for (unsigned j = 0; j < sig.size(); ++j) {
bound_decls.insert(sig[j]);
}
for_each_expr(collect_decls, m_relation_info[i].m_body);
}
for (unsigned i = 0; i < rules.size(); ++i) {
bound_decls.insert(rules[i]->get_decl());
}
for (unsigned i = 0; i < rules.size(); ++i) {
unsigned u_sz = rules[i]->get_uninterpreted_tail_size();
unsigned t_sz = rules[i]->get_tail_size();
for (unsigned j = u_sz; j < t_sz; ++j) {
for_each_expr(collect_decls, rules[i]->get_tail(j));
}
}
smt2_pp_environment_dbg env(m);
func_decl_set::iterator it = aux_decls.begin(), end = aux_decls.end();
for (; it != end; ++it) {
func_decl* f = *it;
ast_smt2_pp(out, f, env);
out << "\n";
}
out << to_string() << "\n";
for (unsigned i = 0; i < rules.size(); ++i) {
out << "(push)\n";
out << "(assert (not\n";
rm.display_smt2(*rules[i], out);
out << "))\n";
out << "(check-sat)\n";
out << "(pop)\n";
}
}
manager::manager(smt_params& fparams, unsigned max_num_contexts, ast_manager& manager) :
m(manager),
m_fparams(fparams),
m_brwr(m),
m_mux(m),
m_background(m.mk_true(), m),
m_contexts(fparams, max_num_contexts, m),
m_next_unique_num(0)
{
}
void manager::add_new_state(func_decl * s) {
SASSERT(s->get_arity()==0); //we currently don't support non-constant states
decl_vector vect;
SASSERT(o_index(0)==1); //we assume this in the number of retrieved symbols
m_mux.create_tuple(s, s->get_arity(), s->get_domain(), s->get_range(), 2, vect);
m_o0_preds.push_back(vect[o_index(0)]);
}
func_decl * manager::get_o_pred(func_decl* s, unsigned idx)
{
func_decl * res = m_mux.try_get_by_prefix(s, o_index(idx));
if(res) { return res; }
add_new_state(s);
res = m_mux.try_get_by_prefix(s, o_index(idx));
SASSERT(res);
return res;
}
func_decl * manager::get_n_pred(func_decl* s)
{
func_decl * res = m_mux.try_get_by_prefix(s, n_index());
if(res) { return res; }
add_new_state(s);
res = m_mux.try_get_by_prefix(s, n_index());
SASSERT(res);
return res;
}
void manager::mk_model_into_cube(const expr_ref_vector & mdl, expr_ref & res) {
m_brwr.mk_and(mdl.size(), mdl.c_ptr(), res);
}
void manager::mk_core_into_cube(const expr_ref_vector & core, expr_ref & res) {
m_brwr.mk_and(core.size(), core.c_ptr(), res);
}
void manager::mk_cube_into_lemma(expr * cube, expr_ref & res) {
m_brwr.mk_not(cube, res);
}
void manager::mk_lemma_into_cube(expr * lemma, expr_ref & res) {
m_brwr.mk_not(lemma, res);
}
expr_ref manager::mk_and(unsigned sz, expr* const* exprs) {
expr_ref result(m);
m_brwr.mk_and(sz, exprs, result);
return result;
}
expr_ref manager::mk_or(unsigned sz, expr* const* exprs) {
expr_ref result(m);
m_brwr.mk_or(sz, exprs, result);
return result;
}
expr_ref manager::mk_not_and(expr_ref_vector const& conjs) {
expr_ref result(m), e(m);
expr_ref_vector es(conjs);
flatten_and(es);
for (unsigned i = 0; i < es.size(); ++i) {
m_brwr.mk_not(es[i].get(), e);
es[i] = e;
}
m_brwr.mk_or(es.size(), es.c_ptr(), result);
return result;
}
void manager::get_or(expr* e, expr_ref_vector& result) {
result.push_back(e);
for (unsigned i = 0; i < result.size(); ) {
e = result[i].get();
if (m.is_or(e)) {
result.append(to_app(e)->get_num_args(), to_app(e)->get_args());
result[i] = result.back();
result.pop_back();
}
else {
++i;
}
}
}
bool manager::try_get_state_and_value_from_atom(expr * atom0, app *& state, app_ref& value)
{
if(!is_app(atom0)) {
return false;
}
app * atom = to_app(atom0);
expr * arg1;
expr * arg2;
app * candidate_state;
app_ref candidate_value(m);
if(m.is_not(atom, arg1)) {
if(!is_app(arg1)) {
return false;
}
candidate_state = to_app(arg1);
candidate_value = m.mk_false();
}
else if(m.is_eq(atom, arg1, arg2)) {
if(!is_app(arg1) || !is_app(arg2)) {
return false;
}
if(!m_mux.is_muxed(to_app(arg1)->get_decl())) {
std::swap(arg1, arg2);
}
candidate_state = to_app(arg1);
candidate_value = to_app(arg2);
}
else {
candidate_state = atom;
candidate_value = m.mk_true();
}
if(!m_mux.is_muxed(candidate_state->get_decl())) {
return false;
}
state = candidate_state;
value = candidate_value;
return true;
}
bool manager::try_get_state_decl_from_atom(expr * atom, func_decl *& state) {
app_ref dummy_value_holder(m);
app * s;
if(try_get_state_and_value_from_atom(atom, s, dummy_value_holder)) {
state = s->get_decl();
return true;
}
else {
return false;
}
}
bool manager::implication_surely_holds(expr * lhs, expr * rhs, expr * bg) {
smt::kernel sctx(m, get_fparams());
if(bg) {
sctx.assert_expr(bg);
}
sctx.assert_expr(lhs);
expr_ref neg_rhs(m.mk_not(rhs),m);
sctx.assert_expr(neg_rhs);
lbool smt_res = sctx.check();
return smt_res==l_false;
}
};

304
src/muz/pdr/pdr_manager.h
View file

@ -1,304 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_manager.h
Abstract:
A manager class for PDR, taking care of creating of AST
objects and conversions between them.
Author:
Krystof Hoder (t-khoder) 2011-8-25.
Revision History:
--*/
#ifndef PDR_MANAGER_H_
#define PDR_MANAGER_H_
#include <utility>
#include <map>
#include "ast/rewriter/bool_rewriter.h"
#include "ast/rewriter/expr_replacer.h"
#include "ast/expr_substitution.h"
#include "util/map.h"
#include "util/ref_vector.h"
#include "smt/smt_kernel.h"
#include "muz/pdr/pdr_util.h"
#include "muz/pdr/pdr_sym_mux.h"
#include "muz/pdr/pdr_farkas_learner.h"
#include "muz/pdr/pdr_smt_context_manager.h"
#include "muz/base/dl_rule.h"
namespace smt {
class context;
}
namespace pdr {
struct relation_info {
func_decl_ref m_pred;
func_decl_ref_vector m_vars;
expr_ref m_body;
relation_info(ast_manager& m, func_decl* pred, ptr_vector<func_decl> const& vars, expr* b):
m_pred(pred, m), m_vars(m, vars.size(), vars.c_ptr()), m_body(b, m) {}
relation_info(relation_info const& other): m_pred(other.m_pred), m_vars(other.m_vars), m_body(other.m_body) {}
};
class unknown_exception {};
class inductive_property {
ast_manager& m;
model_converter_ref m_mc;
vector<relation_info> m_relation_info;
expr_ref fixup_clauses(expr* property) const;
expr_ref fixup_clause(expr* clause) const;
public:
inductive_property(ast_manager& m, model_converter_ref& mc, vector<relation_info> const& relations):
m(m),
m_mc(mc),
m_relation_info(relations) {}
std::string to_string() const;
expr_ref to_expr() const;
void to_model(model_ref& md) const;
void display(datalog::rule_manager& rm, ptr_vector<datalog::rule> const& rules, std::ostream& out) const;
};
class manager
{
ast_manager& m;
smt_params& m_fparams;
mutable bool_rewriter m_brwr;
sym_mux m_mux;
expr_ref m_background;
decl_vector m_o0_preds;
pdr::smt_context_manager m_contexts;
/** whenever we need an unique number, we get this one and increase */
unsigned m_next_unique_num;
unsigned n_index() const { return 0; }
unsigned o_index(unsigned i) const { return i+1; }
void add_new_state(func_decl * s);
public:
manager(smt_params& fparams, unsigned max_num_contexts, ast_manager & manager);
ast_manager& get_manager() const { return m; }
smt_params& get_fparams() const { return m_fparams; }
bool_rewriter& get_brwr() const { return m_brwr; }
expr_ref mk_and(unsigned sz, expr* const* exprs);
expr_ref mk_and(expr_ref_vector const& exprs) {
return mk_and(exprs.size(), exprs.c_ptr());
}
expr_ref mk_and(expr* a, expr* b) {
expr* args[2] = { a, b };
return mk_and(2, args);
}
expr_ref mk_or(unsigned sz, expr* const* exprs);
expr_ref mk_or(expr_ref_vector const& exprs) {
return mk_or(exprs.size(), exprs.c_ptr());
}
expr_ref mk_not_and(expr_ref_vector const& exprs);
void get_or(expr* e, expr_ref_vector& result);
//"o" predicates stand for the old states and "n" for the new states
func_decl * get_o_pred(func_decl * s, unsigned idx);
func_decl * get_n_pred(func_decl * s);
/**
Marks symbol as non-model which means it will not appear in models collected by
get_state_cube_from_model function.
This is to take care of auxiliary symbols introduced by the disjunction relations
to relativize lemmas coming from disjuncts.
*/
void mark_as_non_model(func_decl * p) {
m_mux.mark_as_non_model(p);
}
func_decl * const * begin_o0_preds() const { return m_o0_preds.begin(); }
func_decl * const * end_o0_preds() const { return m_o0_preds.end(); }
bool is_state_pred(func_decl * p) const { return m_mux.is_muxed(p); }
func_decl * to_o0(func_decl * p) { return m_mux.conv(m_mux.get_primary(p), 0, o_index(0)); }
bool is_o(func_decl * p, unsigned idx) const {
return m_mux.has_index(p, o_index(idx));
}
bool is_o(expr* e, unsigned idx) const {
return is_app(e) && is_o(to_app(e)->get_decl(), idx);
}
bool is_o(func_decl * p) const {
unsigned idx;
return m_mux.try_get_index(p, idx) && idx!=n_index();
}
bool is_o(expr* e) const {
return is_app(e) && is_o(to_app(e)->get_decl());
}
bool is_n(func_decl * p) const {
return m_mux.has_index(p, n_index());
}
bool is_n(expr* e) const {
return is_app(e) && is_n(to_app(e)->get_decl());
}
/** true if p should not appead in models propagates into child relations */
bool is_non_model_sym(func_decl * p) const
{ return m_mux.is_non_model_sym(p); }
/** true if f doesn't contain any n predicates */
bool is_o_formula(expr * f) const {
return !m_mux.contains(f, n_index());
}
/** true if f contains only o state preds of index o_idx */
bool is_o_formula(expr * f, unsigned o_idx) const {
return m_mux.is_homogenous_formula(f, o_index(o_idx));
}
/** true if f doesn't contain any o predicates */
bool is_n_formula(expr * f) const {
return m_mux.is_homogenous_formula(f, n_index());
}
func_decl * o2n(func_decl * p, unsigned o_idx) {
return m_mux.conv(p, o_index(o_idx), n_index());
}
func_decl * o2o(func_decl * p, unsigned src_idx, unsigned tgt_idx) {
return m_mux.conv(p, o_index(src_idx), o_index(tgt_idx));
}
func_decl * n2o(func_decl * p, unsigned o_idx) {
return m_mux.conv(p, n_index(), o_index(o_idx));
}
void formula_o2n(expr * f, expr_ref & result, unsigned o_idx, bool homogenous=true)
{ m_mux.conv_formula(f, o_index(o_idx), n_index(), result, homogenous); }
void formula_n2o(expr * f, expr_ref & result, unsigned o_idx, bool homogenous=true)
{ m_mux.conv_formula(f, n_index(), o_index(o_idx), result, homogenous); }
void formula_n2o(unsigned o_idx, bool homogenous, expr_ref & result)
{ m_mux.conv_formula(result.get(), n_index(), o_index(o_idx), result, homogenous); }
void formula_o2o(expr * src, expr_ref & tgt, unsigned src_idx, unsigned tgt_idx, bool homogenous=true)
{ m_mux.conv_formula(src, o_index(src_idx), o_index(tgt_idx), tgt, homogenous); }
/**
Return true if all state symbols which e contains are of one kind (either "n" or one of "o").
*/
bool is_homogenous_formula(expr * e) const {
return m_mux.is_homogenous_formula(e);
}
/**
Collect indices used in expression.
*/
void collect_indices(expr* e, unsigned_vector& indices) const {
m_mux.collect_indices(e, indices);
}
/**
Collect used variables of each index.
*/
void collect_variables(expr* e, vector<ptr_vector<app> >& vars) const {
m_mux.collect_variables(e, vars);
}
/**
Return true iff both s1 and s2 are either "n" or "o" of the same index.
If one (or both) of them are not state symbol, return false.
*/
bool have_different_state_kinds(func_decl * s1, func_decl * s2) const {
unsigned i1, i2;
return m_mux.try_get_index(s1, i1) && m_mux.try_get_index(s2, i2) && i1!=i2;
}
/**
Increase indexes of state symbols in formula by dist.
The 'N' index becomes 'O' index with number dist-1.
*/
void formula_shift(expr * src, expr_ref & tgt, unsigned dist) {
SASSERT(n_index()==0);
SASSERT(o_index(0)==1);
m_mux.shift_formula(src, dist, tgt);
}
void mk_model_into_cube(const expr_ref_vector & mdl, expr_ref & res);
void mk_core_into_cube(const expr_ref_vector & core, expr_ref & res);
void mk_cube_into_lemma(expr * cube, expr_ref & res);
void mk_lemma_into_cube(expr * lemma, expr_ref & res);
/**
Remove from vec all atoms that do not have an "o" state.
The order of elements in vec may change.
An assumption is that atoms having "o" state of given index
do not have "o" states of other indexes or "n" states.
*/
void filter_o_atoms(expr_ref_vector& vec, unsigned o_idx) const
{ m_mux.filter_idx(vec, o_index(o_idx)); }
void filter_n_atoms(expr_ref_vector& vec) const
{ m_mux.filter_idx(vec, n_index()); }
/**
Partition literals into o_lits and others.
*/
void partition_o_atoms(expr_ref_vector const& lits,
expr_ref_vector& o_lits,
expr_ref_vector& other,
unsigned o_idx) const {
m_mux.partition_o_idx(lits, o_lits, other, o_index(o_idx));
}
void filter_out_non_model_atoms(expr_ref_vector& vec) const
{ m_mux.filter_non_model_lits(vec); }
bool try_get_state_and_value_from_atom(expr * atom, app *& state, app_ref& value);
bool try_get_state_decl_from_atom(expr * atom, func_decl *& state);
std::string pp_model(const model_core & mdl) const
{ return m_mux.pp_model(mdl); }
void set_background(expr* b) { m_background = b; }
expr* get_background() const { return m_background; }
/**
Return true if we can show that lhs => rhs. The function can have false negatives
(i.e. when smt::context returns unknown), but no false positives.
bg is background knowledge and can be null
*/
bool implication_surely_holds(expr * lhs, expr * rhs, expr * bg=nullptr);
unsigned get_unique_num() { return m_next_unique_num++; }
pdr::smt_context* mk_fresh() { return m_contexts.mk_fresh(); }
void collect_statistics(statistics& st) const { m_contexts.collect_statistics(st); }
void reset_statistics() { m_contexts.reset_statistics(); }
};
}
#endif

459
src/muz/pdr/pdr_prop_solver.cpp
View file

@ -1,459 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
prop_solver.cpp
Abstract:
SMT solver abstraction for PDR.
Author:
Krystof Hoder (t-khoder) 2011-8-17.
Revision History:
--*/
#include <sstream>
#include "model/model.h"
#include "muz/pdr/pdr_util.h"
#include "muz/pdr/pdr_prop_solver.h"
#include "ast/ast_smt2_pp.h"
#include "muz/base/dl_util.h"
#include "model/model_pp.h"
#include "smt/params/smt_params.h"
#include "ast/datatype_decl_plugin.h"
#include "ast/bv_decl_plugin.h"
#include "muz/pdr/pdr_farkas_learner.h"
#include "ast/ast_smt2_pp.h"
#include "ast/rewriter/expr_replacer.h"
//
// Auxiliary structure to introduce propositional names for assumptions that are not
// propositional. It is to work with the smt::context's restriction
// that assumptions be propositional literals.
//
namespace pdr {
class prop_solver::safe_assumptions {
prop_solver& s;
ast_manager& m;
expr_ref_vector m_atoms;
expr_ref_vector m_assumptions;
obj_map<app,expr *> m_proxies2expr;
obj_map<expr, app*> m_expr2proxies;
unsigned m_num_proxies;
app * mk_proxy(expr* literal) {
app* res;
SASSERT(!is_var(literal)); //it doesn't make sense to introduce names to variables
if (m_expr2proxies.find(literal, res)) {
return res;
}
SASSERT(s.m_proxies.size() >= m_num_proxies);
if (m_num_proxies == s.m_proxies.size()) {
std::stringstream name;
name << "pdr_proxy_" << s.m_proxies.size();
res = m.mk_const(symbol(name.str().c_str()), m.mk_bool_sort());
s.m_proxies.push_back(res);
s.m_aux_symbols.insert(res->get_decl());
}
else {
res = s.m_proxies[m_num_proxies].get();
}
++m_num_proxies;
m_expr2proxies.insert(literal, res);
m_proxies2expr.insert(res, literal);
expr_ref implies(m.mk_or(m.mk_not(res), literal), m);
s.m_ctx->assert_expr(implies);
m_assumptions.push_back(implies);
TRACE("pdr_verbose", tout << "name asserted " << mk_pp(implies, m) << "\n";);
return res;
}
void mk_safe(expr_ref_vector& conjs) {
flatten_and(conjs);
expand_literals(conjs);
for (unsigned i = 0; i < conjs.size(); ++i) {
expr * lit = conjs[i].get();
expr * lit_core = lit;
m.is_not(lit, lit_core);
SASSERT(!m.is_true(lit));
if (!is_uninterp(lit_core) || to_app(lit_core)->get_num_args() != 0) {
conjs[i] = mk_proxy(lit);
}
}
m_assumptions.append(conjs);
}
expr* apply_accessor(
ptr_vector<func_decl> const& acc,
unsigned j,
func_decl* f,
expr* c) {
if (is_app(c) && to_app(c)->get_decl() == f) {
return to_app(c)->get_arg(j);
}
else {
return m.mk_app(acc[j], c);
}
}
void expand_literals(expr_ref_vector& conjs) {
arith_util arith(m);
datatype_util dt(m);
bv_util bv(m);
expr* e1, *e2, *c, *val;
rational r;
unsigned bv_size;
TRACE("pdr",
tout << "begin expand\n";
for (unsigned i = 0; i < conjs.size(); ++i) {
tout << mk_pp(conjs[i].get(), m) << "\n";
});
for (unsigned i = 0; i < conjs.size(); ++i) {
expr* e = conjs[i].get();
if (m.is_eq(e, e1, e2) && arith.is_int_real(e1)) {
conjs[i] = arith.mk_le(e1,e2);
if (i+1 == conjs.size()) {
conjs.push_back(arith.mk_ge(e1, e2));
}
else {
conjs.push_back(conjs[i+1].get());
conjs[i+1] = arith.mk_ge(e1, e2);
}
++i;
}
else if ((m.is_eq(e, c, val) && is_app(val) && dt.is_constructor(to_app(val))) ||
(m.is_eq(e, val, c) && is_app(val) && dt.is_constructor(to_app(val)))){
func_decl* f = to_app(val)->get_decl();
func_decl* r = dt.get_constructor_is(f);
conjs[i] = m.mk_app(r, c);
ptr_vector<func_decl> const& acc = *dt.get_constructor_accessors(f);
for (unsigned j = 0; j < acc.size(); ++j) {
conjs.push_back(m.mk_eq(apply_accessor(acc, j, f, c), to_app(val)->get_arg(j)));
}
}
else if ((m.is_eq(e, c, val) && bv.is_numeral(val, r, bv_size)) ||
(m.is_eq(e, val, c) && bv.is_numeral(val, r, bv_size))) {
rational two(2);
for (unsigned j = 0; j < bv_size; ++j) {
parameter p(j);
//expr* e = m.mk_app(bv.get_family_id(), OP_BIT2BOOL, 1, &p, 1, &c);
expr* e = m.mk_eq(m.mk_app(bv.get_family_id(), OP_BIT1), bv.mk_extract(j, j, c));
if ((r % two).is_zero()) {
e = m.mk_not(e);
}
r = div(r, two);
if (j == 0) {
conjs[i] = e;
}
else {
conjs.push_back(e);
}
}
}
}
TRACE("pdr",
tout << "end expand\n";
for (unsigned i = 0; i < conjs.size(); ++i) {
tout << mk_pp(conjs[i].get(), m) << "\n";
});
}
public:
safe_assumptions(prop_solver& s, expr_ref_vector const& assumptions):
s(s), m(s.m), m_atoms(assumptions), m_assumptions(m), m_num_proxies(0) {
mk_safe(m_atoms);
}
~safe_assumptions() {
}
expr_ref_vector const& atoms() const { return m_atoms; }
unsigned assumptions_size() const { return m_assumptions.size(); }
expr* assumptions(unsigned i) const { return m_assumptions[i]; }
void undo_proxies(expr_ref_vector& es) {
expr_ref e(m);
expr* r;
for (unsigned i = 0; i < es.size(); ++i) {
e = es[i].get();
if (is_app(e) && m_proxies2expr.find(to_app(e), r)) {
es[i] = r;
}
}
}
void elim_proxies(expr_ref_vector& es) {
expr_substitution sub(m, false, m.proofs_enabled());
proof_ref pr(m);
if (m.proofs_enabled()) {
pr = m.mk_asserted(m.mk_true());
}
obj_map<app,expr*>::iterator it = m_proxies2expr.begin(), end = m_proxies2expr.end();
for (; it != end; ++it) {
sub.insert(it->m_key, m.mk_true(), pr);
}
scoped_ptr<expr_replacer> rep = mk_default_expr_replacer(m);
rep->set_substitution(&sub);
replace_proxies(*rep, es);
}
private:
void replace_proxies(expr_replacer& rep, expr_ref_vector& es) {
expr_ref e(m);
for (unsigned i = 0; i < es.size(); ++i) {
e = es[i].get();
rep(e);
es[i] = e;
if (m.is_true(e)) {
es[i] = es.back();
es.pop_back();
--i;
}
}
}
};
prop_solver::prop_solver(manager& pm, symbol const& name) :
m_fparams(pm.get_fparams()),
m(pm.get_manager()),
m_pm(pm),
m_name(name),
m_ctx(pm.mk_fresh()),
m_pos_level_atoms(m),
m_neg_level_atoms(m),
m_proxies(m),
m_core(nullptr),
m_model(nullptr),
m_consequences(nullptr),
m_subset_based_core(false),
m_use_farkas(false),
m_in_level(false),
m_current_level(0)
{
m_ctx->assert_expr(m_pm.get_background());
}
void prop_solver::add_level() {
unsigned idx = level_cnt();
std::stringstream name;
name << m_name << "#level_" << idx;
func_decl * lev_pred = m.mk_fresh_func_decl(name.str().c_str(), 0, nullptr,m.mk_bool_sort());
m_aux_symbols.insert(lev_pred);
m_level_preds.push_back(lev_pred);
app_ref pos_la(m.mk_const(lev_pred), m);
app_ref neg_la(m.mk_not(pos_la.get()), m);
m_pos_level_atoms.push_back(pos_la);
m_neg_level_atoms.push_back(neg_la);
m_level_atoms_set.insert(pos_la.get());
m_level_atoms_set.insert(neg_la.get());
}
void prop_solver::ensure_level(unsigned lvl) {
while (lvl>=level_cnt()) {
add_level();
}
}
unsigned prop_solver::level_cnt() const {
return m_level_preds.size();
}
void prop_solver::push_level_atoms(unsigned level, expr_ref_vector& tgt) const {
unsigned lev_cnt = level_cnt();
for (unsigned i=0; i<lev_cnt; i++) {
bool active = i>=level;
app * lev_atom = active ? m_neg_level_atoms[i] : m_pos_level_atoms[i];
tgt.push_back(lev_atom);
}
}
void prop_solver::add_formula(expr * form) {
SASSERT(!m_in_level);
m_ctx->assert_expr(form);
IF_VERBOSE(21, verbose_stream() << "$ asserted " << mk_pp(form, m) << "\n";);
TRACE("pdr", tout << "add_formula: " << mk_pp(form, m) << "\n";);
}
void prop_solver::add_level_formula(expr * form, unsigned level) {
ensure_level(level);
app * lev_atom = m_pos_level_atoms[level].get();
app_ref lform(m.mk_or(form, lev_atom), m);
add_formula(lform.get());
}
lbool prop_solver::check_safe_assumptions(
safe_assumptions& safe,
const expr_ref_vector& atoms)
{
flet<bool> _model(m_fparams.m_model, m_model != nullptr);
expr_ref_vector expr_atoms(m);
expr_atoms.append(atoms.size(), atoms.c_ptr());
if (m_in_level) {
push_level_atoms(m_current_level, expr_atoms);
}
lbool result = m_ctx->check(expr_atoms);
TRACE("pdr",
tout << mk_pp(m_pm.mk_and(expr_atoms), m) << "\n";
tout << result << "\n";);
if (result == l_true && m_model) {
m_ctx->get_model(*m_model);
TRACE("pdr_verbose", model_pp(tout, **m_model); );
}
if (result == l_false) {
unsigned core_size = m_ctx->get_unsat_core_size();
m_assumes_level = false;
for (unsigned i = 0; i < core_size; ++i) {
if (m_level_atoms_set.contains(m_ctx->get_unsat_core_expr(i))) {
m_assumes_level = true;
break;
}
}
}
if (result == l_false &&
m_core &&
m.proofs_enabled() &&
m_use_farkas &&
!m_subset_based_core) {
extract_theory_core(safe);
}
else if (result == l_false && m_core) {
extract_subset_core(safe);
SASSERT(expr_atoms.size() >= m_core->size());
}
m_core = nullptr;
m_model = nullptr;
m_subset_based_core = false;
return result;
}
void prop_solver::extract_subset_core(safe_assumptions& safe) {
unsigned core_size = m_ctx->get_unsat_core_size();
m_core->reset();
for (unsigned i = 0; i < core_size; ++i) {
expr * core_expr = m_ctx->get_unsat_core_expr(i);
SASSERT(is_app(core_expr));
if (m_level_atoms_set.contains(core_expr)) {
continue;
}
if (m_ctx->is_aux_predicate(core_expr)) {
continue;
}
m_core->push_back(to_app(core_expr));
}
safe.undo_proxies(*m_core);
TRACE("pdr",
tout << "core_exprs: ";
for (unsigned i = 0; i < core_size; ++i) {
tout << mk_pp(m_ctx->get_unsat_core_expr(i), m) << " ";
}
tout << "\n";
tout << "core: " << mk_pp(m_pm.mk_and(*m_core), m) << "\n";
);
}
void prop_solver::extract_theory_core(safe_assumptions& safe) {
proof_ref pr(m);
pr = m_ctx->get_proof();
IF_VERBOSE(21, verbose_stream() << mk_ismt2_pp(pr, m) << "\n";);
farkas_learner fl(m_fparams, m);
expr_ref_vector lemmas(m);
obj_hashtable<expr> bs;
for (unsigned i = 0; i < safe.assumptions_size(); ++i) {
bs.insert(safe.assumptions(i));
}
fl.get_lemmas(pr, bs, lemmas);
safe.elim_proxies(lemmas);
fl.simplify_lemmas(lemmas); // redundant?
bool outside_of_logic =
(m_fparams.m_arith_mode == AS_DIFF_LOGIC &&
!is_difference_logic(m, lemmas.size(), lemmas.c_ptr())) ||
(m_fparams.m_arith_mode == AS_UTVPI &&
!is_utvpi_logic(m, lemmas.size(), lemmas.c_ptr()));
if (outside_of_logic) {
IF_VERBOSE(2,
verbose_stream() << "not diff\n";
for (unsigned i = 0; i < lemmas.size(); ++i) {
verbose_stream() << mk_pp(lemmas[i].get(), m) << "\n";
});
extract_subset_core(safe);
}
else {
IF_VERBOSE(2,
verbose_stream() << "Lemmas\n";
for (unsigned i = 0; i < lemmas.size(); ++i) {
verbose_stream() << mk_pp(lemmas[i].get(), m) << "\n";
});
m_core->reset();
m_core->append(lemmas);
if (m_consequences) {
fl.get_consequences(pr, bs, *m_consequences);
}
}
}
lbool prop_solver::check_assumptions(const expr_ref_vector & atoms) {
return check_assumptions_and_formula(atoms, m.mk_true());
}
lbool prop_solver::check_conjunction_as_assumptions(expr * conj) {
expr_ref_vector asmp(m);
asmp.push_back(conj);
return check_assumptions(asmp);
}
lbool prop_solver::check_assumptions_and_formula(const expr_ref_vector & atoms, expr * form)
{
pdr::smt_context::scoped _scoped(*m_ctx);
safe_assumptions safe(*this, atoms);
m_ctx->assert_expr(form);
CTRACE("pdr", !m.is_true(form), tout << "check with formula: " << mk_pp(form, m) << "\n";);
lbool res = check_safe_assumptions(safe, safe.atoms());
//
// we don't have to undo model naming, as from the model
// we extract the values for state variables directly
//
return res;
}
void prop_solver::collect_statistics(statistics& st) const {
}
void prop_solver::reset_statistics() {
}
}

139
src/muz/pdr/pdr_prop_solver.h
View file

@ -1,139 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
prop_solver.h
Abstract:
SAT solver abstraction for PDR.
Author:
Krystof Hoder (t-khoder) 2011-8-17.
Revision History:
--*/
#ifndef PROP_SOLVER_H_
#define PROP_SOLVER_H_
#include <map>
#include <string>
#include <utility>
#include "ast/ast.h"
#include "util/obj_hashtable.h"
#include "smt/smt_kernel.h"
#include "util/util.h"
#include "util/vector.h"
#include "muz/pdr/pdr_manager.h"
#include "muz/pdr/pdr_smt_context_manager.h"
namespace pdr {
class prop_solver {
private:
smt_params& m_fparams;
ast_manager& m;
manager& m_pm;
symbol m_name;
scoped_ptr<pdr::smt_context> m_ctx;
decl_vector m_level_preds;
app_ref_vector m_pos_level_atoms; // atoms used to identify level
app_ref_vector m_neg_level_atoms; //
obj_hashtable<expr> m_level_atoms_set;
app_ref_vector m_proxies; // predicates for assumptions
expr_ref_vector* m_core;
model_ref* m_model;
expr_ref_vector* m_consequences;
bool m_subset_based_core;
bool m_assumes_level;
bool m_use_farkas;
func_decl_set m_aux_symbols;
bool m_in_level;
unsigned m_current_level; // set when m_in_level
/** Add level atoms activating certain level into a vector */
void push_level_atoms(unsigned level, expr_ref_vector & tgt) const;
void ensure_level(unsigned lvl);
class safe_assumptions;
void extract_theory_core(safe_assumptions& assumptions);
void extract_subset_core(safe_assumptions& assumptions);
lbool check_safe_assumptions(
safe_assumptions& assumptions,
expr_ref_vector const& atoms);
public:
prop_solver(pdr::manager& pm, symbol const& name);
/** return true is s is a symbol introduced by prop_solver */
bool is_aux_symbol(func_decl * s) const {
return
m_aux_symbols.contains(s) ||
m_ctx->is_aux_predicate(s);
}
void set_core(expr_ref_vector* core) { m_core = core; }
void set_model(model_ref* mdl) { m_model = mdl; }
void set_subset_based_core(bool f) { m_subset_based_core = f; }
void set_consequences(expr_ref_vector* consequences) { m_consequences = consequences; }
bool assumes_level() const { return m_assumes_level; }
void add_level();
unsigned level_cnt() const;
class scoped_level {
bool& m_lev;
public:
scoped_level(prop_solver& ps, unsigned lvl):m_lev(ps.m_in_level) {
SASSERT(!m_lev); m_lev = true; ps.m_current_level = lvl;
}
~scoped_level() { m_lev = false; }
};
void set_use_farkas(bool f) { m_use_farkas = f; }
bool get_use_farkas() const { return m_use_farkas; }
void add_formula(expr * form);
void add_level_formula(expr * form, unsigned level);
/**
* Return true iff conjunction of atoms is consistent with the current state of
* the solver.
*
* If the conjunction of atoms is inconsistent with the solver state and core is non-zero,
* core will contain an unsatisfiable core of atoms.
*
* If the conjunction of atoms is consistent with the solver state and o_model is non-zero,
* o_model will contain the "o" literals true in the assignment.
*/
lbool check_assumptions(const expr_ref_vector & atoms);
lbool check_conjunction_as_assumptions(expr * conj);
/**
* Like check_assumptions, except it also asserts an extra formula
*/
lbool check_assumptions_and_formula(
const expr_ref_vector & atoms,
expr * form);
void collect_statistics(statistics& st) const;
void reset_statistics();
};
}
#endif

132
src/muz/pdr/pdr_reachable_cache.cpp
View file

@ -1,132 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
reachable_cache.cpp
Abstract:
Object for caching of reachable states.
Author:
Krystof Hoder (t-khoder) 2011-9-14.
Revision History:
--*/
#include "muz/pdr/pdr_reachable_cache.h"
namespace pdr {
reachable_cache::reachable_cache(pdr::manager & pm, datalog::PDR_CACHE_MODE cm)
: m(pm.get_manager()),
m_pm(pm),
m_ctx(nullptr),
m_ref_holder(m),
m_disj_connector(m),
m_cache_mode(cm) {
if (m_cache_mode == datalog::CONSTRAINT_CACHE) {
m_ctx = pm.mk_fresh();
m_ctx->assert_expr(m_pm.get_background());
}
}
void reachable_cache::add_disjuncted_formula(expr * f) {
app_ref new_connector(m.mk_fresh_const("disj_conn", m.mk_bool_sort()), m);
app_ref neg_new_connector(m.mk_not(new_connector), m);
app_ref extended_form(m);
if(m_disj_connector) {
extended_form = m.mk_or(m_disj_connector, neg_new_connector, f);
}
else {
extended_form = m.mk_or(neg_new_connector, f);
}
if (m_ctx) {
m_ctx->assert_expr(extended_form);
}
m_disj_connector = new_connector;
}
void reachable_cache::add_reachable(expr * cube) {
switch (m_cache_mode) {
case datalog::NO_CACHE:
break;
case datalog::HASH_CACHE:
m_stats.m_inserts++;
m_cache.insert(cube);
m_ref_holder.push_back(cube);
break;
case datalog::CONSTRAINT_CACHE:
m_stats.m_inserts++;
TRACE("pdr", tout << mk_pp(cube, m) << "\n";);
add_disjuncted_formula(cube);
break;
default:
UNREACHABLE();
}
}
bool reachable_cache::is_reachable(expr * cube) {
bool found = false;
switch (m_cache_mode) {
case datalog::NO_CACHE:
return false;
case datalog::HASH_CACHE:
found = m_cache.contains(cube);
break;
case datalog::CONSTRAINT_CACHE: {
if(!m_disj_connector) {
found = false;
break;
}
expr * connector = m_disj_connector.get();
expr_ref_vector assms(m);
assms.push_back(connector);
m_ctx->push();
m_ctx->assert_expr(cube);
lbool res = m_ctx->check(assms);
m_ctx->pop();
TRACE("pdr", tout << "is_reachable: " << res << " " << mk_pp(cube, m) << "\n";);
found = res == l_true;
break;
}
default:
UNREACHABLE();
break;
}
if (found) {
m_stats.m_hits++;
}
else {
m_stats.m_miss++;
}
return found;
}
void reachable_cache::collect_statistics(statistics& st) const {
st.update("cache inserts", m_stats.m_inserts);
st.update("cache miss", m_stats.m_miss);
st.update("cache hits", m_stats.m_hits);
}
void reachable_cache::reset_statistics() {
m_stats.reset();
}
}

66
src/muz/pdr/pdr_reachable_cache.h
View file

@ -1,66 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
reachable_cache.h
Abstract:
Object for caching of reachable states.
Author:
Krystof Hoder (t-khoder) 2011-9-14.
Revision History:
--*/
#ifndef REACHABLE_CACHE_H_
#define REACHABLE_CACHE_H_
#include "ast/ast.h"
#include "util/ref_vector.h"
#include "muz/pdr/pdr_manager.h"
#include "muz/pdr/pdr_smt_context_manager.h"
namespace pdr {
class reachable_cache {
struct stats {
unsigned m_hits;
unsigned m_miss;
unsigned m_inserts;
stats() { reset(); }
void reset() { memset(this, 0, sizeof(*this)); }
};
ast_manager & m;
manager & m_pm;
scoped_ptr<smt_context> m_ctx;
ast_ref_vector m_ref_holder;
app_ref m_disj_connector;
obj_hashtable<expr> m_cache;
stats m_stats;
datalog::PDR_CACHE_MODE m_cache_mode;
void add_disjuncted_formula(expr * f);
public:
reachable_cache(pdr::manager & pm, datalog::PDR_CACHE_MODE cm);
void add_init(app * f) { add_disjuncted_formula(f); }
/** add cube whose all models are reachable */
void add_reachable(expr * cube);
/** return true if there is a model of cube which is reachable */
bool is_reachable(expr * cube);
void collect_statistics(statistics& st) const;
void reset_statistics();
};
}
#endif

167
src/muz/pdr/pdr_smt_context_manager.cpp
View file

@ -1,167 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_smt_context_manager.cpp
Abstract:
Manager of smt contexts
Author:
Nikolaj Bjorner (nbjorner) 2011-11-26.
Revision History:
--*/
#include "muz/pdr/pdr_smt_context_manager.h"
#include "ast/has_free_vars.h"
#include "ast/ast_pp.h"
#include "ast/ast_smt_pp.h"
#include <sstream>
#include "smt/params/smt_params.h"
namespace pdr {
smt_context::smt_context(smt_context_manager& p, ast_manager& m, app* pred):
m_pred(pred, m),
m_parent(p),
m_in_delay_scope(false),
m_pushed(false)
{}
bool smt_context::is_aux_predicate(func_decl* p) {
return m_parent.is_aux_predicate(p);
}
smt_context::scoped::scoped(smt_context& ctx): m_ctx(ctx) {
SASSERT(!m_ctx.m_in_delay_scope);
SASSERT(!m_ctx.m_pushed);
m_ctx.m_in_delay_scope = true;
}
smt_context::scoped::~scoped() {
SASSERT(m_ctx.m_in_delay_scope);
if (m_ctx.m_pushed) {
m_ctx.pop();
m_ctx.m_pushed = false;
}
m_ctx.m_in_delay_scope = false;
}
_smt_context::_smt_context(smt::kernel & ctx, smt_context_manager& p, app* pred):
smt_context(p, ctx.m(), pred),
m_context(ctx)
{}
void _smt_context::assert_expr(expr* e) {
ast_manager& m = m_context.m();
if (m.is_true(e)) {
return;
}
CTRACE("pdr", has_free_vars(e), tout << mk_pp(e, m) << "\n";);
SASSERT(!has_free_vars(e));
if (m_in_delay_scope && !m_pushed) {
m_context.push();
m_pushed = true;
}
expr_ref fml(m);
fml = m_pushed?e:m.mk_implies(m_pred, e);
m_context.assert_expr(fml);
}
lbool _smt_context::check(expr_ref_vector& assumptions) {
ast_manager& m = m_pred.get_manager();
if (!m.is_true(m_pred)) {
assumptions.push_back(m_pred);
}
TRACE("pdr_check",
{
ast_smt_pp pp(m);
for (unsigned i = 0; i < m_context.size(); ++i) {
pp.add_assumption(m_context.get_formula(i));
}
for (unsigned i = 0; i < assumptions.size(); ++i) {
pp.add_assumption(assumptions[i].get());
}
static unsigned lemma_id = 0;
std::ostringstream strm;
strm << "pdr-lemma-" << lemma_id << ".smt2";
std::ofstream out(strm.str().c_str());
pp.display_smt2(out, m.mk_true());
out.close();
lemma_id++;
tout << "pdr_check: " << strm.str() << "\n";
});
lbool result = m_context.check(assumptions.size(), assumptions.c_ptr());
if (!m.is_true(m_pred)) {
assumptions.pop_back();
}
return result;
}
void _smt_context::get_model(model_ref& model) {
m_context.get_model(model);
}
proof* _smt_context::get_proof() {
return m_context.get_proof();
}
smt_context_manager::smt_context_manager(smt_params& fp, unsigned max_num_contexts, ast_manager& m):
m_fparams(fp),
m(m),
m_max_num_contexts(max_num_contexts),
m_num_contexts(0),
m_predicate_list(m) {
}
smt_context_manager::~smt_context_manager() {
TRACE("pdr",tout << "\n";);
std::for_each(m_contexts.begin(), m_contexts.end(), delete_proc<smt::kernel>());
}
smt_context* smt_context_manager::mk_fresh() {
++m_num_contexts;
app_ref pred(m);
smt::kernel * ctx = nullptr;
if (m_max_num_contexts == 0) {
m_contexts.push_back(alloc(smt::kernel, m, m_fparams));
pred = m.mk_true();
ctx = m_contexts[m_num_contexts-1];
}
else {
if (m_contexts.size() < m_max_num_contexts) {
m_contexts.push_back(alloc(smt::kernel, m, m_fparams));
}
std::stringstream name;
name << "#context" << m_num_contexts;
pred = m.mk_const(symbol(name.str().c_str()), m.mk_bool_sort());
m_predicate_list.push_back(pred);
m_predicate_set.insert(pred->get_decl());
ctx = m_contexts[(m_num_contexts-1)%m_max_num_contexts];
}
return alloc(_smt_context, *ctx, *this, pred);
}
void smt_context_manager::collect_statistics(statistics& st) const {
for (unsigned i = 0; i < m_contexts.size(); ++i) {
m_contexts[i]->collect_statistics(st);
}
}
void smt_context_manager::reset_statistics() {
for (unsigned i = 0; i < m_contexts.size(); ++i) {
m_contexts[i]->reset_statistics();
}
}
};

92
src/muz/pdr/pdr_smt_context_manager.h
View file

@ -1,92 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_smt_context_manager.h
Abstract:
Manager of smt contexts
Author:
Nikolaj Bjorner (nbjorner) 2011-11-26.
Revision History:
--*/
#ifndef PDR_SMT_CONTEXT_MANAGER_H_
#define PDR_SMT_CONTEXT_MANAGER_H_
#include "smt/smt_kernel.h"
#include "ast/func_decl_dependencies.h"
#include "muz/base/dl_util.h"
namespace pdr {
class smt_context_manager;
class smt_context {
protected:
app_ref m_pred;
smt_context_manager& m_parent;
bool m_in_delay_scope;
bool m_pushed;
public:
smt_context(smt_context_manager& p, ast_manager& m, app* pred);
virtual ~smt_context() {}
virtual void assert_expr(expr* e) = 0;
virtual lbool check(expr_ref_vector& assumptions) = 0;
virtual void get_model(model_ref& model) = 0;
virtual proof* get_proof() = 0;
virtual unsigned get_unsat_core_size() = 0;
virtual expr* get_unsat_core_expr(unsigned i) = 0;
virtual void push() = 0;
virtual void pop() = 0;
bool is_aux_predicate(func_decl* p);
bool is_aux_predicate(expr* p) { return is_app(p) && is_aux_predicate(to_app(p)->get_decl()); }
class scoped {
smt_context& m_ctx;
public:
scoped(smt_context& ctx);
~scoped();
};
};
class _smt_context : public smt_context {
smt::kernel & m_context;
public:
_smt_context(smt::kernel & ctx, smt_context_manager& p, app* pred);
~_smt_context() override {}
void assert_expr(expr* e) override;
lbool check(expr_ref_vector& assumptions) override;
void get_model(model_ref& model) override;
proof* get_proof() override;
void push() override { m_context.push(); }
void pop() override { m_context.pop(1); }
unsigned get_unsat_core_size() override { return m_context.get_unsat_core_size(); }
expr* get_unsat_core_expr(unsigned i) override { return m_context.get_unsat_core_expr(i); }
};
class smt_context_manager {
smt_params& m_fparams;
ast_manager& m;
unsigned m_max_num_contexts;
ptr_vector<smt::kernel> m_contexts;
unsigned m_num_contexts;
app_ref_vector m_predicate_list;
func_decl_set m_predicate_set;
public:
smt_context_manager(smt_params& fp, unsigned max_num_contexts, ast_manager& m);
~smt_context_manager();
smt_context* mk_fresh();
void collect_statistics(statistics& st) const;
void reset_statistics();
bool is_aux_predicate(func_decl* p) const { return m_predicate_set.contains(p); }
};
};
#endif

601
src/muz/pdr/pdr_sym_mux.cpp
View file

@ -1,601 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
sym_mux.cpp
Abstract:
A symbol multiplexer that helps with having multiple versions of each of a set of symbols.
Author:
Krystof Hoder (t-khoder) 2011-9-8.
Revision History:
--*/
#include <sstream>
#include "ast/ast_pp.h"
#include "ast/for_each_expr.h"
#include "model/model.h"
#include "ast/rewriter/rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "muz/pdr/pdr_util.h"
#include "muz/pdr/pdr_sym_mux.h"
using namespace pdr;
sym_mux::sym_mux(ast_manager & m)
: m(m), m_ref_holder(m),
m_next_sym_suffix_idx(0) {
m_suffixes.push_back("_n");
size_t suf_sz = m_suffixes.size();
for(unsigned i = 0; i < suf_sz; ++i) {
symbol suff_sym = symbol(m_suffixes[i].c_str());
m_used_suffixes.insert(suff_sym);
}
}
std::string sym_mux::get_suffix(unsigned i) {
while(m_suffixes.size() <= i) {
std::string new_suffix;
symbol new_syffix_sym;
do {
std::stringstream stm;
stm<<'_'<<m_next_sym_suffix_idx;
m_next_sym_suffix_idx++;
new_suffix = stm.str();
new_syffix_sym = symbol(new_suffix.c_str());
}
while (m_used_suffixes.contains(new_syffix_sym));
m_used_suffixes.insert(new_syffix_sym);
m_suffixes.push_back(new_suffix);
}
std::string result = m_suffixes[i];
return result;
}
void sym_mux::create_tuple(func_decl* prefix, unsigned arity, sort * const * domain, sort * range,
unsigned tuple_length, decl_vector & tuple)
{
SASSERT(tuple_length>0);
while(tuple.size()<tuple_length) {
tuple.push_back(0);
}
SASSERT(tuple.size()==tuple_length);
std::string pre = prefix->get_name().str();
for(unsigned i=0; i<tuple_length; i++) {
if (tuple[i] != 0) {
SASSERT(tuple[i]->get_arity()==arity);
SASSERT(tuple[i]->get_range()==range);
//domain should match as well, but we won't bother checking an array equality
}
else {
std::string name = pre+get_suffix(i);
tuple[i] = m.mk_func_decl(symbol(name.c_str()), arity, domain, range);
}
m_ref_holder.push_back(tuple[i]);
m_sym2idx.insert(tuple[i], i);
m_sym2prim.insert(tuple[i], tuple[0]);
}
m_prim2all.insert(tuple[0], tuple);
m_prefix2prim.insert(prefix, tuple[0]);
m_prim2prefix.insert(tuple[0], prefix);
m_prim_preds.push_back(tuple[0]);
m_ref_holder.push_back(prefix);
}
void sym_mux::ensure_tuple_size(func_decl * prim, unsigned sz) {
SASSERT(m_prim2all.contains(prim));
decl_vector& tuple = m_prim2all.find_core(prim)->get_data().m_value;
SASSERT(tuple[0]==prim);
if(sz <= tuple.size()) { return; }
func_decl * prefix;
TRUSTME(m_prim2prefix.find(prim, prefix));
std::string prefix_name = prefix->get_name().bare_str();
for(unsigned i = tuple.size(); i < sz; ++i) {
std::string name = prefix_name + get_suffix(i);
func_decl * new_sym = m.mk_func_decl(symbol(name.c_str()), prefix->get_arity(),
prefix->get_domain(), prefix->get_range());
tuple.push_back(new_sym);
m_ref_holder.push_back(new_sym);
m_sym2idx.insert(new_sym, i);
m_sym2prim.insert(new_sym, prim);
}
}
func_decl * sym_mux::conv(func_decl * sym, unsigned src_idx, unsigned tgt_idx)
{
if(src_idx==tgt_idx) { return sym; }
func_decl * prim = (src_idx==0) ? sym : get_primary(sym);
if(tgt_idx>src_idx) {
ensure_tuple_size(prim, tgt_idx+1);
}
decl_vector & sym_vect = m_prim2all.find_core(prim)->get_data().m_value;
SASSERT(sym_vect[src_idx]==sym);
return sym_vect[tgt_idx];
}
func_decl * sym_mux::get_or_create_symbol_by_prefix(func_decl* prefix, unsigned idx,
unsigned arity, sort * const * domain, sort * range)
{
func_decl * prim = try_get_primary_by_prefix(prefix);
if(prim) {
SASSERT(prim->get_arity()==arity);
SASSERT(prim->get_range()==range);
//domain should match as well, but we won't bother checking an array equality
return conv(prim, 0, idx);
}
decl_vector syms;
create_tuple(prefix, arity, domain, range, idx+1, syms);
return syms[idx];
}
bool sym_mux::is_muxed_lit(expr * e, unsigned idx) const
{
if(!is_app(e)) { return false; }
app * a = to_app(e);
if(m.is_not(a) && is_app(a->get_arg(0))) {
a = to_app(a->get_arg(0));
}
return is_muxed(a->get_decl());
}
struct sym_mux::formula_checker
{
formula_checker(const sym_mux & parent, bool all, unsigned idx) :
m_parent(parent), m_all(all), m_idx(idx),
m_found_what_needed(false)
{
}
void operator()(expr * e)
{
if(m_found_what_needed || !is_app(e)) { return; }
func_decl * sym = to_app(e)->get_decl();
unsigned sym_idx;
if(!m_parent.try_get_index(sym, sym_idx)) { return; }
bool have_idx = sym_idx==m_idx;
if( m_all ? (!have_idx) : have_idx ) {
m_found_what_needed = true;
}
}
bool all_have_idx() const
{
SASSERT(m_all); //we were looking for the queried property
return !m_found_what_needed;
}
bool some_with_idx() const
{
SASSERT(!m_all); //we were looking for the queried property
return m_found_what_needed;
}
private:
const sym_mux & m_parent;
bool m_all;
unsigned m_idx;
/**
If we check whether all muxed symbols are of given index, we look for
counter-examples, checking whether form contains a muxed symbol of an index,
we look for symbol of index m_idx.
*/
bool m_found_what_needed;
};
bool sym_mux::contains(expr * e, unsigned idx) const
{
formula_checker chck(*this, false, idx);
for_each_expr(chck, m_visited, e);
m_visited.reset();
return chck.some_with_idx();
}
bool sym_mux::is_homogenous_formula(expr * e, unsigned idx) const
{
formula_checker chck(*this, true, idx);
for_each_expr(chck, m_visited, e);
m_visited.reset();
return chck.all_have_idx();
}
bool sym_mux::is_homogenous(const expr_ref_vector & vect, unsigned idx) const
{
expr * const * begin = vect.c_ptr();
expr * const * end = begin + vect.size();
for(expr * const * it = begin; it!=end; it++) {
if(!is_homogenous_formula(*it, idx)) {
return false;
}
}
return true;
}
class sym_mux::index_collector {
sym_mux const& m_parent;
svector<bool> m_indices;
public:
index_collector(sym_mux const& s):
m_parent(s) {}
void operator()(expr * e) {
if (is_app(e)) {
func_decl * sym = to_app(e)->get_decl();
unsigned idx;
if (m_parent.try_get_index(sym, idx)) {
SASSERT(idx > 0);
--idx;
if (m_indices.size() <= idx) {
m_indices.resize(idx+1, false);
}
m_indices[idx] = true;
}
}
}
void extract(unsigned_vector& indices) {
for (unsigned i = 0; i < m_indices.size(); ++i) {
if (m_indices[i]) {
indices.push_back(i);
}
}
}
};
void sym_mux::collect_indices(expr* e, unsigned_vector& indices) const {
indices.reset();
index_collector collector(*this);
for_each_expr(collector, m_visited, e);
m_visited.reset();
collector.extract(indices);
}
class sym_mux::variable_collector {
sym_mux const& m_parent;
vector<ptr_vector<app> >& m_vars;
public:
variable_collector(sym_mux const& s, vector<ptr_vector<app> >& vars):
m_parent(s), m_vars(vars) {}
void operator()(expr * e) {
if (is_app(e)) {
func_decl * sym = to_app(e)->get_decl();
unsigned idx;
if (m_parent.try_get_index(sym, idx)) {
SASSERT(idx > 0);
--idx;
if (m_vars.size() <= idx) {
m_vars.resize(idx+1, ptr_vector<app>());
}
m_vars[idx].push_back(to_app(e));
}
}
}
};
void sym_mux::collect_variables(expr* e, vector<ptr_vector<app> >& vars) const {
vars.reset();
variable_collector collector(*this, vars);
for_each_expr(collector, m_visited, e);
m_visited.reset();
}
class sym_mux::hmg_checker {
const sym_mux & m_parent;
bool m_found_idx;
unsigned m_idx;
bool m_multiple_indexes;
public:
hmg_checker(const sym_mux & parent) :
m_parent(parent), m_found_idx(false), m_multiple_indexes(false)
{
}
void operator()(expr * e)
{
if(m_multiple_indexes || !is_app(e)) { return; }
func_decl * sym = to_app(e)->get_decl();
unsigned sym_idx;
if(!m_parent.try_get_index(sym, sym_idx)) { return; }
if(!m_found_idx) {
m_found_idx = true;
m_idx = sym_idx;
return;
}
if(m_idx==sym_idx) { return; }
m_multiple_indexes = true;
}
bool has_multiple_indexes() const
{
return m_multiple_indexes;
}
};
bool sym_mux::is_homogenous_formula(expr * e) const {
hmg_checker chck(*this);
for_each_expr(chck, m_visited, e);
m_visited.reset();
return !chck.has_multiple_indexes();
}
struct sym_mux::conv_rewriter_cfg : public default_rewriter_cfg
{
private:
ast_manager & m;
sym_mux & m_parent;
unsigned m_from_idx;
unsigned m_to_idx;
bool m_homogenous;
public:
conv_rewriter_cfg(sym_mux & parent, unsigned from_idx, unsigned to_idx, bool homogenous)
: m(parent.get_manager()),
m_parent(parent),
m_from_idx(from_idx),
m_to_idx(to_idx),
m_homogenous(homogenous) {}
bool get_subst(expr * s, expr * & t, proof * & t_pr) {
if(!is_app(s)) { return false; }
app * a = to_app(s);
func_decl * sym = a->get_decl();
if(!m_parent.has_index(sym, m_from_idx)) {
(void) m_homogenous;
SASSERT(!m_homogenous || !m_parent.is_muxed(sym));
return false;
}
func_decl * tgt = m_parent.conv(sym, m_from_idx, m_to_idx);
t = m.mk_app(tgt, a->get_args());
return true;
}
};
void sym_mux::conv_formula(expr * f, unsigned src_idx, unsigned tgt_idx, expr_ref & res, bool homogenous)
{
if(src_idx==tgt_idx) {
res = f;
return;
}
conv_rewriter_cfg r_cfg(*this, src_idx, tgt_idx, homogenous);
rewriter_tpl<conv_rewriter_cfg> rwr(m, false, r_cfg);
rwr(f, res);
}
struct sym_mux::shifting_rewriter_cfg : public default_rewriter_cfg
{
private:
ast_manager & m;
sym_mux & m_parent;
int m_shift;
public:
shifting_rewriter_cfg(sym_mux & parent, int shift)
: m(parent.get_manager()),
m_parent(parent),
m_shift(shift) {}
bool get_subst(expr * s, expr * & t, proof * & t_pr) {
if(!is_app(s)) { return false; }
app * a = to_app(s);
func_decl * sym = a->get_decl();
unsigned idx;
if(!m_parent.try_get_index(sym, idx)) {
return false;
}
SASSERT(static_cast<int>(idx)+m_shift>=0);
func_decl * tgt = m_parent.conv(sym, idx, idx+m_shift);
t = m.mk_app(tgt, a->get_args());
return true;
}
};
void sym_mux::shift_formula(expr * f, int dist, expr_ref & res)
{
if(dist==0) {
res = f;
return;
}
shifting_rewriter_cfg r_cfg(*this, dist);
rewriter_tpl<shifting_rewriter_cfg> rwr(m, false, r_cfg);
rwr(f, res);
}
void sym_mux::conv_formula_vector(const expr_ref_vector & vect, unsigned src_idx, unsigned tgt_idx,
expr_ref_vector & res)
{
res.reset();
expr * const * begin = vect.c_ptr();
expr * const * end = begin + vect.size();
for(expr * const * it = begin; it!=end; it++) {
expr_ref converted(m);
conv_formula(*it, src_idx, tgt_idx, converted);
res.push_back(converted);
}
}
void sym_mux::filter_idx(expr_ref_vector & vect, unsigned idx) const {
unsigned i = 0;
while (i < vect.size()) {
expr* e = vect[i].get();
if (contains(e, idx) && is_homogenous_formula(e, idx)) {
i++;
}
else {
// we don't allow mixing states inside vector elements
SASSERT(!contains(e, idx));
vect[i] = vect.back();
vect.pop_back();
}
}
}
void sym_mux::partition_o_idx(
expr_ref_vector const& lits,
expr_ref_vector& o_lits,
expr_ref_vector& other, unsigned idx) const {
for (unsigned i = 0; i < lits.size(); ++i) {
if (contains(lits[i], idx) && is_homogenous_formula(lits[i], idx)) {
o_lits.push_back(lits[i]);
}
else {
other.push_back(lits[i]);
}
}
}
class sym_mux::nonmodel_sym_checker {
const sym_mux & m_parent;
bool m_found;
public:
nonmodel_sym_checker(const sym_mux & parent) :
m_parent(parent), m_found(false) {
}
void operator()(expr * e) {
if(m_found || !is_app(e)) { return; }
func_decl * sym = to_app(e)->get_decl();
if(m_parent.is_non_model_sym(sym)) {
m_found = true;
}
}
bool found() const {
return m_found;
}
};
bool sym_mux::has_nonmodel_symbol(expr * e) const {
nonmodel_sym_checker chck(*this);
for_each_expr(chck, e);
return chck.found();
}
void sym_mux::filter_non_model_lits(expr_ref_vector & vect) const {
unsigned i = 0;
while (i < vect.size()) {
if (!has_nonmodel_symbol(vect[i].get())) {
i++;
}
else {
vect[i] = vect.back();
vect.pop_back();
}
}
}
class sym_mux::decl_idx_comparator
{
const sym_mux & m_parent;
public:
decl_idx_comparator(const sym_mux & parent)
: m_parent(parent)
{ }
bool operator()(func_decl * sym1, func_decl * sym2)
{
unsigned idx1, idx2;
if (!m_parent.try_get_index(sym1, idx1)) { idx1 = UINT_MAX; }
if (!m_parent.try_get_index(sym2, idx2)) { idx2 = UINT_MAX; }
if (idx1 != idx2) { return idx1<idx2; }
return lt(sym1->get_name(), sym2->get_name());
}
};
std::string sym_mux::pp_model(const model_core & mdl) const {
decl_vector consts;
unsigned sz = mdl.get_num_constants();
for (unsigned i = 0; i < sz; i++) {
func_decl * d = mdl.get_constant(i);
consts.push_back(d);
}
std::sort(consts.begin(), consts.end(), decl_idx_comparator(*this));
std::stringstream res;
decl_vector::iterator end = consts.end();
for (decl_vector::iterator it = consts.begin(); it!=end; it++) {
func_decl * d = *it;
std::string name = d->get_name().str();
const char * arrow = " -> ";
res << name << arrow;
unsigned indent = static_cast<unsigned>(name.length() + strlen(arrow));
res << mk_pp(mdl.get_const_interp(d), m, indent) << "\n";
if (it+1 != end) {
unsigned idx1, idx2;
if (!try_get_index(*it, idx1)) { idx1 = UINT_MAX; }
if (!try_get_index(*(it+1), idx2)) { idx2 = UINT_MAX; }
if (idx1 != idx2) { res << "\n"; }
}
}
return res.str();
}
#if 0
class sym_mux::index_renamer_cfg : public default_rewriter_cfg{
const sym_mux & m_parent;
unsigned m_idx;
public:
index_renamer_cfg(const sym_mux & p, unsigned idx) : m_parent(p), m_idx(idx) {}
bool get_subst(expr * s, expr * & t, proof * & t_pr) {
if (!is_app(s)) return false;
app * a = to_app(s);
if (a->get_family_id() != null_family_id) {
return false;
}
func_decl * sym = a->get_decl();
unsigned idx;
if(!m_parent.try_get_index(sym, idx)) {
return false;
}
if (m_idx == idx) {
return false;
}
ast_manager& m = m_parent.get_manager();
symbol name = symbol((sym->get_name().str() + "!").c_str());
func_decl * tgt = m.mk_func_decl(name, sym->get_arity(), sym->get_domain(), sym->get_range());
t = m.mk_app(tgt, a->get_num_args(), a->get_args());
return true;
}
};
#endif

247
src/muz/pdr/pdr_sym_mux.h
View file

@ -1,247 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
sym_mux.h
Abstract:
A symbol multiplexer that helps with having multiple versions of each of a set of symbols.
Author:
Krystof Hoder (t-khoder) 2011-9-8.
Revision History:
--*/
#ifndef SYM_MUX_H_
#define SYM_MUX_H_
#include "ast/ast.h"
#include "util/map.h"
#include "util/vector.h"
#include <vector>
class model_core;
namespace pdr {
class sym_mux
{
public:
typedef ptr_vector<app> app_vector;
typedef ptr_vector<func_decl> decl_vector;
private:
typedef obj_map<func_decl,unsigned> sym2u;
typedef obj_map<func_decl, decl_vector> sym2dv;
typedef obj_map<func_decl,func_decl *> sym2sym;
typedef obj_map<func_decl, func_decl *> sym2pred;
typedef hashtable<symbol, symbol_hash_proc, symbol_eq_proc> symbols;
ast_manager & m;
mutable ast_ref_vector m_ref_holder;
mutable expr_mark m_visited;
mutable unsigned m_next_sym_suffix_idx;
mutable symbols m_used_suffixes;
/** Here we have default suffixes for each of the variants */
std::vector<std::string> m_suffixes;
/**
Primary symbol is the 0-th variant. This member maps from primary symbol
to vector of all its variants (including the primary variant).
*/
sym2dv m_prim2all;
/**
For each symbol contains its variant index
*/
mutable sym2u m_sym2idx;
/**
For each symbol contains its primary variant
*/
mutable sym2sym m_sym2prim;
/**
Maps prefixes passed to the create_tuple to
the primary symbol created from it.
*/
sym2pred m_prefix2prim;
/**
Maps pripary symbols to prefixes that were used to create them.
*/
sym2sym m_prim2prefix;
decl_vector m_prim_preds;
obj_hashtable<func_decl> m_non_model_syms;
struct formula_checker;
struct conv_rewriter_cfg;
struct shifting_rewriter_cfg;
class decl_idx_comparator;
class hmg_checker;
class nonmodel_sym_checker;
class index_renamer_cfg;
class index_collector;
class variable_collector;
std::string get_suffix(unsigned i);
void ensure_tuple_size(func_decl * prim, unsigned sz);
public:
sym_mux(ast_manager & m);
ast_manager & get_manager() const { return m; }
bool is_muxed(func_decl * sym) const { return m_sym2idx.contains(sym); }
bool try_get_index(func_decl * sym, unsigned & idx) const {
return m_sym2idx.find(sym,idx);
}
bool has_index(func_decl * sym, unsigned idx) const {
unsigned actual_idx;
return try_get_index(sym, actual_idx) && idx==actual_idx;
}
/** Return primary symbol. sym must be muxed. */
func_decl * get_primary(func_decl * sym) const {
func_decl * prim;
TRUSTME(m_sym2prim.find(sym, prim));
return prim;
}
/**
Return primary symbol created from prefix, or 0 if the prefix was never used.
*/
func_decl * try_get_primary_by_prefix(func_decl* prefix) const {
func_decl * res;
if(!m_prefix2prim.find(prefix, res)) {
return nullptr;
}
return res;
}
/**
Return symbol created from prefix, or 0 if the prefix was never used.
*/
func_decl * try_get_by_prefix(func_decl* prefix, unsigned idx) {
func_decl * prim = try_get_primary_by_prefix(prefix);
if(!prim) {
return nullptr;
}
return conv(prim, 0, idx);
}
/**
Marks symbol as non-model which means it will not appear in models collected by
get_muxed_cube_from_model function.
This is to take care of auxiliary symbols introduced by the disjunction relations
to relativize lemmas coming from disjuncts.
*/
void mark_as_non_model(func_decl * sym) {
SASSERT(is_muxed(sym));
m_non_model_syms.insert(get_primary(sym));
}
func_decl * get_or_create_symbol_by_prefix(func_decl* prefix, unsigned idx,
unsigned arity, sort * const * domain, sort * range);
bool is_muxed_lit(expr * e, unsigned idx) const;
bool is_non_model_sym(func_decl * s) const {
return is_muxed(s) && m_non_model_syms.contains(get_primary(s));
}
/**
Create a multiplexed tuple of propositional constants.
Symbols may be suplied in the tuple vector,
those beyond the size of the array and those with corresponding positions
assigned to zero will be created using prefix.
Tuple length must be at least one.
*/
void create_tuple(func_decl* prefix, unsigned arity, sort * const * domain, sort * range,
unsigned tuple_length, decl_vector & tuple);
/**
Return true if the only multiplexed symbols which e contains are of index idx.
*/
bool is_homogenous_formula(expr * e, unsigned idx) const;
bool is_homogenous(const expr_ref_vector & vect, unsigned idx) const;
/**
Return true if all multiplexed symbols which e contains are of one index.
*/
bool is_homogenous_formula(expr * e) const;
/**
Return true if expression e contains a muxed symbol of index idx.
*/
bool contains(expr * e, unsigned idx) const;
/**
Collect indices used in expression.
*/
void collect_indices(expr* e, unsigned_vector& indices) const;
/**
Collect used variables of each index.
*/
void collect_variables(expr* e, vector<ptr_vector<app> >& vars) const;
/**
Convert symbol sym which has to be of src_idx variant into variant tgt_idx.
*/
func_decl * conv(func_decl * sym, unsigned src_idx, unsigned tgt_idx);
/**
Convert src_idx symbols in formula f variant into tgt_idx.
If homogenous is true, formula cannot contain symbols of other variants.
*/
void conv_formula(expr * f, unsigned src_idx, unsigned tgt_idx, expr_ref & res, bool homogenous=true);
void conv_formula_vector(const expr_ref_vector & vect, unsigned src_idx, unsigned tgt_idx,
expr_ref_vector & res);
/**
Shifts the muxed symbols in f by dist. Dist can be negative, but it should never shift
symbol index to a negative value.
*/
void shift_formula(expr * f, int dist, expr_ref & res);
/**
Remove from vect literals (atoms or negations of atoms) of symbols
that contain multiplexed symbols with indexes other than idx.
Each of the literals can contain only symbols multiplexed with one index
(this trivially holds if the literals are propositional).
Order of elements in vect may be modified by this function
*/
void filter_idx(expr_ref_vector & vect, unsigned idx) const;
/**
Partition literals into o_literals and others.
*/
void partition_o_idx(expr_ref_vector const& lits,
expr_ref_vector& o_lits,
expr_ref_vector& other, unsigned idx) const;
bool has_nonmodel_symbol(expr * e) const;
void filter_non_model_lits(expr_ref_vector & vect) const;
func_decl * const * begin_prim_preds() const { return m_prim_preds.begin(); }
func_decl * const * end_prim_preds() const { return m_prim_preds.end(); }
std::string pp_model(const model_core & mdl) const;
};
}
#endif

508
src/muz/pdr/pdr_util.cpp
View file

@ -1,508 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_util.cpp
Abstract:
Utility functions for PDR.
Author:
Krystof Hoder (t-khoder) 2011-8-19.
Revision History:
Notes:
--*/
#include <sstream>
#include "util/util.h"
#include "util/ref_vector.h"
#include "ast/array_decl_plugin.h"
#include "ast/ast_pp.h"
#include "ast/for_each_expr.h"
#include "ast/scoped_proof.h"
#include "ast/arith_decl_plugin.h"
#include "ast/rewriter/expr_replacer.h"
#include "ast/rewriter/bool_rewriter.h"
#include "ast/rewriter/poly_rewriter.h"
#include "ast/rewriter/poly_rewriter_def.h"
#include "ast/rewriter/arith_rewriter.h"
#include "ast/rewriter/rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "smt/params/smt_params.h"
#include "model/model.h"
#include "muz/base/dl_util.h"
#include "muz/pdr/pdr_manager.h"
#include "muz/pdr/pdr_util.h"
#include "model/model_smt2_pp.h"
namespace pdr {
unsigned ceil_log2(unsigned u) {
if (u == 0) { return 0; }
unsigned pow2 = next_power_of_two(u);
return get_num_1bits(pow2-1);
}
std::string pp_cube(const ptr_vector<expr>& model, ast_manager& m) {
return pp_cube(model.size(), model.c_ptr(), m);
}
std::string pp_cube(const expr_ref_vector& model, ast_manager& m) {
return pp_cube(model.size(), model.c_ptr(), m);
}
std::string pp_cube(const app_ref_vector& model, ast_manager& m) {
return pp_cube(model.size(), model.c_ptr(), m);
}
std::string pp_cube(const app_vector& model, ast_manager& m) {
return pp_cube(model.size(), model.c_ptr(), m);
}
std::string pp_cube(unsigned sz, app * const * lits, ast_manager& m) {
return pp_cube(sz, (expr * const *)(lits), m);
}
std::string pp_cube(unsigned sz, expr * const * lits, ast_manager& m) {
std::stringstream res;
res << "(";
expr * const * end = lits+sz;
for (expr * const * it = lits; it!=end; it++) {
res << mk_pp(*it, m);
if (it+1!=end) {
res << ", ";
}
}
res << ")";
return res.str();
}
void reduce_disequalities(model& model, unsigned threshold, expr_ref& fml) {
ast_manager& m = fml.get_manager();
expr_ref_vector conjs(m);
flatten_and(fml, conjs);
obj_map<expr, unsigned> diseqs;
expr* n, *lhs, *rhs;
for (unsigned i = 0; i < conjs.size(); ++i) {
if (m.is_not(conjs[i].get(), n) &&
m.is_eq(n, lhs, rhs)) {
if (!m.is_value(rhs)) {
std::swap(lhs, rhs);
}
if (!m.is_value(rhs)) {
continue;
}
diseqs.insert_if_not_there2(lhs, 0)->get_data().m_value++;
}
}
expr_substitution sub(m);
unsigned orig_size = conjs.size();
unsigned num_deleted = 0;
expr_ref val(m), tmp(m);
proof_ref pr(m);
pr = m.mk_asserted(m.mk_true());
obj_map<expr, unsigned>::iterator it = diseqs.begin();
obj_map<expr, unsigned>::iterator end = diseqs.end();
for (; it != end; ++it) {
if (it->m_value >= threshold) {
model.eval(it->m_key, val);
sub.insert(it->m_key, val, pr);
conjs.push_back(m.mk_eq(it->m_key, val));
num_deleted += it->m_value;
}
}
if (orig_size < conjs.size()) {
scoped_ptr<expr_replacer> rep = mk_expr_simp_replacer(m);
rep->set_substitution(&sub);
for (unsigned i = 0; i < orig_size; ++i) {
tmp = conjs[i].get();
(*rep)(tmp);
if (m.is_true(tmp)) {
conjs[i] = conjs.back();
SASSERT(orig_size <= conjs.size());
conjs.pop_back();
SASSERT(orig_size <= 1 + conjs.size());
if (i + 1 == orig_size) {
// no-op.
}
else if (orig_size <= conjs.size()) {
// no-op
}
else {
SASSERT(orig_size == 1 + conjs.size());
--orig_size;
--i;
}
}
else {
conjs[i] = tmp;
}
}
IF_VERBOSE(2, verbose_stream() << "Deleted " << num_deleted << " disequalities " << conjs.size() << " conjuncts\n";);
}
fml = m.mk_and(conjs.size(), conjs.c_ptr());
}
class test_diff_logic {
ast_manager& m;
arith_util a;
bv_util bv;
bool m_is_dl;
bool m_test_for_utvpi;
bool is_numeric(expr* e) const {
if (a.is_numeral(e)) {
return true;
}
expr* cond, *th, *el;
if (m.is_ite(e, cond, th, el)) {
return is_numeric(th) && is_numeric(el);
}
return false;
}
bool is_arith_expr(expr *e) const {
return is_app(e) && a.get_family_id() == to_app(e)->get_family_id();
}
bool is_offset(expr* e) const {
if (a.is_numeral(e)) {
return true;
}
expr* cond, *th, *el, *e1, *e2;
if (m.is_ite(e, cond, th, el)) {
return is_offset(th) && is_offset(el);
}
// recognize offsets.
if (a.is_add(e, e1, e2)) {
if (is_numeric(e1)) {
return is_offset(e2);
}
if (is_numeric(e2)) {
return is_offset(e1);
}
return false;
}
if (m_test_for_utvpi) {
if (a.is_mul(e, e1, e2)) {
if (is_minus_one(e1)) {
return is_offset(e2);
}
if (is_minus_one(e2)) {
return is_offset(e1);
}
}
}
return !is_arith_expr(e);
}
bool is_minus_one(expr const * e) const {
rational r; return a.is_numeral(e, r) && r.is_minus_one();
}
bool test_ineq(expr* e) const {
SASSERT(a.is_le(e) || a.is_ge(e) || m.is_eq(e));
SASSERT(to_app(e)->get_num_args() == 2);
expr * lhs = to_app(e)->get_arg(0);
expr * rhs = to_app(e)->get_arg(1);
if (is_offset(lhs) && is_offset(rhs))
return true;
if (!is_numeric(rhs))
std::swap(lhs, rhs);
if (!is_numeric(rhs))
return false;
// lhs can be 'x' or '(+ x (* -1 y))'
if (is_offset(lhs))
return true;
expr* arg1, *arg2;
if (!a.is_add(lhs, arg1, arg2))
return false;
// x
if (m_test_for_utvpi) {
return is_offset(arg1) && is_offset(arg2);
}
if (is_arith_expr(arg1))
std::swap(arg1, arg2);
if (is_arith_expr(arg1))
return false;
// arg2: (* -1 y)
expr* m1, *m2;
if (!a.is_mul(arg2, m1, m2))
return false;
return is_minus_one(m1) && is_offset(m2);
}
bool test_eq(expr* e) const {
expr* lhs = nullptr, *rhs = nullptr;
VERIFY(m.is_eq(e, lhs, rhs));
if (!a.is_int_real(lhs)) {
return true;
}
if (a.is_numeral(lhs) || a.is_numeral(rhs)) {
return test_ineq(e);
}
return
test_term(lhs) &&
test_term(rhs) &&
!a.is_mul(lhs) &&
!a.is_mul(rhs);
}
bool test_term(expr* e) const {
if (m.is_bool(e)) {
return true;
}
if (a.is_numeral(e)) {
return true;
}
if (is_offset(e)) {
return true;
}
expr* lhs, *rhs;
if (a.is_add(e, lhs, rhs)) {
if (!a.is_numeral(lhs)) {
std::swap(lhs, rhs);
}
return a.is_numeral(lhs) && is_offset(rhs);
}
if (a.is_mul(e, lhs, rhs)) {
return is_minus_one(lhs) || is_minus_one(rhs);
}
return false;
}
bool is_non_arith_or_basic(expr* e) {
if (!is_app(e)) {
return false;
}
family_id fid = to_app(e)->get_family_id();
if (fid == null_family_id &&
!m.is_bool(e) &&
to_app(e)->get_num_args() > 0) {
return true;
}
return
fid != m.get_basic_family_id() &&
fid != null_family_id &&
fid != a.get_family_id() &&
fid != bv.get_family_id();
}
public:
test_diff_logic(ast_manager& m): m(m), a(m), bv(m), m_is_dl(true), m_test_for_utvpi(false) {}
void test_for_utvpi() { m_test_for_utvpi = true; }
void operator()(expr* e) {
if (!m_is_dl) {
return;
}
if (a.is_le(e) || a.is_ge(e)) {
m_is_dl = test_ineq(e);
}
else if (m.is_eq(e)) {
m_is_dl = test_eq(e);
}
else if (is_non_arith_or_basic(e)) {
m_is_dl = false;
}
else if (is_app(e)) {
app* a = to_app(e);
for (unsigned i = 0; m_is_dl && i < a->get_num_args(); ++i) {
m_is_dl = test_term(a->get_arg(i));
}
}
if (!m_is_dl) {
char const* msg = "non-diff: ";
if (m_test_for_utvpi) {
msg = "non-utvpi: ";
}
IF_VERBOSE(1, verbose_stream() << msg << mk_pp(e, m) << "\n";);
}
}
bool is_dl() const { return m_is_dl; }
};
bool is_difference_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls) {
test_diff_logic test(m);
expr_fast_mark1 mark;
for (unsigned i = 0; i < num_fmls; ++i) {
quick_for_each_expr(test, mark, fmls[i]);
}
return test.is_dl();
}
bool is_utvpi_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls) {
test_diff_logic test(m);
test.test_for_utvpi();
expr_fast_mark1 mark;
for (unsigned i = 0; i < num_fmls; ++i) {
quick_for_each_expr(test, mark, fmls[i]);
}
return test.is_dl();
}
class arith_normalizer : public poly_rewriter<arith_rewriter_core> {
ast_manager& m;
arith_util m_util;
enum op_kind { LE, GE, EQ };
public:
arith_normalizer(ast_manager& m, params_ref const& p = params_ref()): poly_rewriter<arith_rewriter_core>(m, p), m(m), m_util(m) {}
br_status mk_app_core(func_decl* f, unsigned num_args, expr* const* args, expr_ref& result) {
br_status st = BR_FAILED;
if (m.is_eq(f)) {
SASSERT(num_args == 2); return mk_eq_core(args[0], args[1], result);
}
if (f->get_family_id() != get_fid()) {
return st;
}
switch (f->get_decl_kind()) {
case OP_NUM: st = BR_FAILED; break;
case OP_IRRATIONAL_ALGEBRAIC_NUM: st = BR_FAILED; break;
case OP_LE: SASSERT(num_args == 2); st = mk_le_core(args[0], args[1], result); break;
case OP_GE: SASSERT(num_args == 2); st = mk_ge_core(args[0], args[1], result); break;
case OP_LT: SASSERT(num_args == 2); st = mk_lt_core(args[0], args[1], result); break;
case OP_GT: SASSERT(num_args == 2); st = mk_gt_core(args[0], args[1], result); break;
default: st = BR_FAILED; break;
}
return st;
}
private:
br_status mk_eq_core(expr* arg1, expr* arg2, expr_ref& result) {
return mk_le_ge_eq_core(arg1, arg2, EQ, result);
}
br_status mk_le_core(expr* arg1, expr* arg2, expr_ref& result) {
return mk_le_ge_eq_core(arg1, arg2, LE, result);
}
br_status mk_ge_core(expr* arg1, expr* arg2, expr_ref& result) {
return mk_le_ge_eq_core(arg1, arg2, GE, result);
}
br_status mk_lt_core(expr* arg1, expr* arg2, expr_ref& result) {
result = m.mk_not(m_util.mk_ge(arg1, arg2));
return BR_REWRITE2;
}
br_status mk_gt_core(expr* arg1, expr* arg2, expr_ref& result) {
result = m.mk_not(m_util.mk_le(arg1, arg2));
return BR_REWRITE2;
}
br_status mk_le_ge_eq_core(expr* arg1, expr* arg2, op_kind kind, expr_ref& result) {
if (m_util.is_real(arg1)) {
numeral g(0);
get_coeffs(arg1, g);
get_coeffs(arg2, g);
if (!g.is_one() && !g.is_zero()) {
SASSERT(g.is_pos());
expr_ref new_arg1 = rdiv_polynomial(arg1, g);
expr_ref new_arg2 = rdiv_polynomial(arg2, g);
switch(kind) {
case LE: result = m_util.mk_le(new_arg1, new_arg2); return BR_DONE;
case GE: result = m_util.mk_ge(new_arg1, new_arg2); return BR_DONE;
case EQ: result = m_util.mk_eq(new_arg1, new_arg2); return BR_DONE;
}
}
}
return BR_FAILED;
}
void update_coeff(numeral const& r, numeral& g) {
if (g.is_zero() || abs(r) < g) {
g = abs(r);
}
}
void get_coeffs(expr* e, numeral& g) {
rational r;
unsigned sz;
expr* const* args = get_monomials(e, sz);
for (unsigned i = 0; i < sz; ++i) {
expr* arg = args[i];
if (!m_util.is_numeral(arg, r)) {
get_power_product(arg, r);
}
update_coeff(r, g);
}
}
expr_ref rdiv_polynomial(expr* e, numeral const& g) {
rational r;
SASSERT(g.is_pos());
SASSERT(!g.is_one());
expr_ref_vector monomes(m);
unsigned sz;
expr* const* args = get_monomials(e, sz);
for (unsigned i = 0; i < sz; ++i) {
expr* arg = args[i];
if (m_util.is_numeral(arg, r)) {
monomes.push_back(m_util.mk_numeral(r/g, false));
}
else {
expr* p = get_power_product(arg, r);
r /= g;
if (r.is_one()) {
monomes.push_back(p);
}
else {
monomes.push_back(m_util.mk_mul(m_util.mk_numeral(r, false), p));
}
}
}
expr_ref result(m);
mk_add(monomes.size(), monomes.c_ptr(), result);
return result;
}
};
struct arith_normalizer_cfg: public default_rewriter_cfg {
arith_normalizer m_r;
bool rewrite_patterns() const { return false; }
br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result, proof_ref & result_pr) {
return m_r.mk_app_core(f, num, args, result);
}
arith_normalizer_cfg(ast_manager & m, params_ref const & p):m_r(m,p) {}
};
class arith_normalizer_star : public rewriter_tpl<arith_normalizer_cfg> {
arith_normalizer_cfg m_cfg;
public:
arith_normalizer_star(ast_manager & m, params_ref const & p):
rewriter_tpl<arith_normalizer_cfg>(m, false, m_cfg),
m_cfg(m, p) {}
};
void normalize_arithmetic(expr_ref& t) {
ast_manager& m = t.get_manager();
scoped_no_proof _sp(m);
params_ref p;
arith_normalizer_star rw(m, p);
expr_ref tmp(m);
rw(t, tmp);
t = tmp;
}
}
template class rewriter_tpl<pdr::arith_normalizer_cfg>;

81
src/muz/pdr/pdr_util.h
View file

@ -1,81 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
pdr_util.h
Abstract:
Utility functions for PDR.
Author:
Krystof Hoder (t-khoder) 2011-8-19.
Revision History:
--*/
#ifndef PDR_UTIL_H_
#define PDR_UTIL_H_
#include "ast/ast.h"
#include "ast/ast_pp.h"
#include "ast/ast_util.h"
#include "util/obj_hashtable.h"
#include "util/ref_vector.h"
#include "util/trace.h"
#include "util/vector.h"
#include "ast/arith_decl_plugin.h"
#include "ast/array_decl_plugin.h"
#include "ast/bv_decl_plugin.h"
class model;
class model_core;
namespace pdr {
/**
* Return the ceiling of base 2 logarithm of a number,
* or zero if the nmber is zero.
*/
unsigned ceil_log2(unsigned u);
typedef ptr_vector<app> app_vector;
typedef ptr_vector<func_decl> decl_vector;
typedef obj_hashtable<func_decl> func_decl_set;
std::string pp_cube(const ptr_vector<expr>& model, ast_manager& manager);
std::string pp_cube(const expr_ref_vector& model, ast_manager& manager);
std::string pp_cube(const ptr_vector<app>& model, ast_manager& manager);
std::string pp_cube(const app_ref_vector& model, ast_manager& manager);
std::string pp_cube(unsigned sz, app * const * lits, ast_manager& manager);
std::string pp_cube(unsigned sz, expr * const * lits, ast_manager& manager);
/**
\brief replace variables that are used in many disequalities by
an equality using the model.
Assumption: the model satisfies the conjunctions.
*/
void reduce_disequalities(model& model, unsigned threshold, expr_ref& fml);
/**
\brief normalize coefficients in polynomials so that least coefficient is 1.
*/
void normalize_arithmetic(expr_ref& t);
/**
\brief determine if formulas belong to difference logic or UTVPI fragment.
*/
bool is_difference_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls);
bool is_utvpi_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls);
}
#endif

2
src/muz/rel/udoc_relation.cpp
View file

@ -869,7 +869,7 @@ namespace datalog {
dm.set(*d, idx, BIT_1);
result.intersect(dm, *d);
}
else if ((m.is_eq(g, e1, e2) || m.is_iff(g, e1, e2)) && m.is_bool(e1)) {
else if (m.is_iff(g, e1, e2)) {
udoc diff1, diff2;
diff1.push_back(dm.allocateX());
diff2.push_back(dm.allocateX());

13
src/muz/spacer/CMakeLists.txt
View file

@ -8,18 +8,25 @@ z3_add_component(spacer
spacer_generalizers.cpp
spacer_manager.cpp
spacer_prop_solver.cpp
spacer_smt_context_manager.cpp
spacer_sym_mux.cpp
spacer_util.cpp
spacer_itp_solver.cpp
spacer_virtual_solver.cpp
spacer_iuc_solver.cpp
spacer_legacy_mbp.cpp
spacer_proof_utils.cpp
spacer_unsat_core_learner.cpp
spacer_unsat_core_plugin.cpp
spacer_matrix.cpp
spacer_antiunify.cpp
spacer_mev_array.cpp
spacer_qe_project.cpp
spacer_sem_matcher.cpp
spacer_quant_generalizer.cpp
spacer_callback.cpp
spacer_json.cpp
spacer_iuc_proof.cpp
spacer_mbc.cpp
spacer_pdr.cpp
spacer_sat_answer.cpp
COMPONENT_DEPENDENCIES
arith_tactics
core_tactics

309
src/muz/spacer/spacer_antiunify.cpp
View file

@ -28,6 +28,7 @@ Revision History:
namespace spacer {
// Abstracts numeric values by variables
struct var_abs_rewriter : public default_rewriter_cfg {
ast_manager &m;
@ -56,8 +57,8 @@ struct var_abs_rewriter : public default_rewriter_cfg {
{
bool contains_const_child = false;
app* a = to_app(t);
for (unsigned i=0, sz = a->get_num_args(); i < sz; ++i) {
if (m_util.is_numeral(a->get_arg(i))) {
for (expr * arg : *a) {
if (m_util.is_numeral(arg)) {
contains_const_child = true;
}
}
@ -102,190 +103,73 @@ struct var_abs_rewriter : public default_rewriter_cfg {
};
/*
* construct m_g, which is a generalization of t, where every constant
* is replaced by a variable for any variable in m_g, remember the
* substitution to get back t and save it in m_substitutions
*/
anti_unifier::anti_unifier(expr* t, ast_manager& man) : m(man), m_pinned(m), m_g(m)
{
m_pinned.push_back(t);
obj_map<expr, expr*> substitution;
anti_unifier::anti_unifier(ast_manager &manager) : m(manager), m_pinned(m) {}
var_abs_rewriter var_abs_cfg(m, substitution);
rewriter_tpl<var_abs_rewriter> var_abs_rw (m, false, var_abs_cfg);
var_abs_rw (t, m_g);
m_substitutions.push_back(substitution); //TODO: refactor into vector, remove k
void anti_unifier::reset() {
m_subs.reset();
m_cache.reset();
m_todo.reset();
m_pinned.reset();
}
/* traverses m_g and t in parallel. if they only differ in constants
* (i.e. m_g contains a variable, where t contains a constant), then
* add the substitutions, which need to be applied to m_g to get t, to
* m_substitutions.
*/
bool anti_unifier::add_term(expr* t) {
m_pinned.push_back(t);
void anti_unifier::operator()(expr *e1, expr *e2, expr_ref &res,
substitution &s1, substitution &s2) {
ptr_vector<expr> todo;
ptr_vector<expr> todo2;
todo.push_back(m_g);
todo2.push_back(t);
reset();
if (e1 == e2) {res = e1; s1.reset(); s2.reset(); return;}
ast_mark visited;
m_todo.push_back(expr_pair(e1, e2));
while (!m_todo.empty()) {
const expr_pair &p = m_todo.back();
SASSERT(is_app(p.first));
SASSERT(is_app(p.second));
arith_util util(m);
app * n1 = to_app(p.first);
app * n2 = to_app(p.second);
obj_map<expr, expr*> substitution;
while (!todo.empty()) {
expr* current = todo.back();
todo.pop_back();
expr* current2 = todo2.back();
todo2.pop_back();
if (!visited.is_marked(current)) {
visited.mark(current, true);
if (is_var(current)) {
// TODO: for now we don't allow variables in the terms we want to antiunify
SASSERT(m_substitutions[0].contains(current));
if (util.is_numeral(current2)) {
substitution.insert(current, current2);
}
else {return false;}
}
else {
SASSERT(is_app(current));
if (is_app(current2) &&
to_app(current)->get_decl() == to_app(current2)->get_decl() &&
to_app(current)->get_num_args() == to_app(current2)->get_num_args()) {
// TODO: what to do for numerals here? E.g. if we
// have 1 and 2, do they have the same decl or are
// the decls already different?
SASSERT (!util.is_numeral(current) || current == current2);
for (unsigned i = 0, num_args = to_app(current)->get_num_args();
i < num_args; ++i) {
todo.push_back(to_app(current)->get_arg(i));
todo2.push_back(to_app(current2)->get_arg(i));
}
}
else {
return false;
}
}
}
}
// we now know that the terms can be anti-unified, so add the cached substitution
m_substitutions.push_back(substitution);
return true;
}
/*
* returns m_g, where additionally any variable, which has only equal
* substitutions, is substituted with that substitution
*/
void anti_unifier::finalize() {
ptr_vector<expr> todo;
todo.push_back(m_g);
ast_mark visited;
obj_map<expr, expr*> generalization;
arith_util util(m);
// post-order traversel which ignores constants and handles them
// directly when the enclosing term of the constant is handled
while (!todo.empty()) {
expr* current = todo.back();
SASSERT(is_app(current));
// if we haven't already visited current
if (!visited.is_marked(current)) {
bool existsUnvisitedParent = false;
for (unsigned i = 0, sz = to_app(current)->get_num_args(); i < sz; ++i) {
expr* argument = to_app(current)->get_arg(i);
if (!is_var(argument)) {
SASSERT(is_app(argument));
// if we haven't visited the current parent yet
if(!visited.is_marked(argument)) {
// add it to the stack
todo.push_back(argument);
existsUnvisitedParent = true;
}
}
}
// if we already visited all parents, we can visit current too
if (!existsUnvisitedParent) {
visited.mark(current, true);
todo.pop_back();
ptr_buffer<expr> arg_list;
for (unsigned i = 0, num_args = to_app(current)->get_num_args();
i < num_args; ++i) {
expr* argument = to_app(current)->get_arg(i);
if (is_var(argument)) {
// compute whether there are different
// substitutions for argument
bool containsDifferentSubstitutions = false;
for (unsigned i=0, sz = m_substitutions.size(); i+1 < sz; ++i) {
SASSERT(m_substitutions[i].contains(argument));
SASSERT(m_substitutions[i+1].contains(argument));
// TODO: how to check equality?
if (m_substitutions[i][argument] !=
m_substitutions[i+1][argument])
{
containsDifferentSubstitutions = true;
break;
}
}
// if yes, use the variable
if (containsDifferentSubstitutions) {
arg_list.push_back(argument);
}
// otherwise use the concrete value instead
// and remove the substitutions
else
{
arg_list.push_back(m_substitutions[0][argument]);
for (unsigned i=0, sz = m_substitutions.size(); i < sz; ++i) {
SASSERT(m_substitutions[i].contains(argument));
m_substitutions[i].remove(argument);
}
}
}
else {
SASSERT(generalization.contains(argument));
arg_list.push_back(generalization[argument]);
}
}
SASSERT(to_app(current)->get_num_args() == arg_list.size());
expr_ref application(m.mk_app(to_app(current)->get_decl(),
to_app(current)->get_num_args(),
arg_list.c_ptr()), m);
m_pinned.push_back(application);
generalization.insert(current, application);
}
unsigned num_arg1 = n1->get_num_args();
unsigned num_arg2 = n2->get_num_args();
if (n1->get_decl() != n2->get_decl() || num_arg1 != num_arg2) {
expr_ref v(m);
v = m.mk_var(m_subs.size(), get_sort(n1));
m_pinned.push_back(v);
m_subs.push_back(expr_pair(n1, n2));
m_cache.insert(n1, n2, v);
}
else {
todo.pop_back();
expr *tmp;
unsigned todo_sz = m_todo.size();
ptr_buffer<expr> kids;
for (unsigned i = 0; i < num_arg1; ++i) {
expr *arg1 = n1->get_arg(i);
expr *arg2 = n2->get_arg(i);
if (arg1 == arg2) {kids.push_back(arg1);}
else if (m_cache.find(arg1, arg2, tmp)) {kids.push_back(tmp);}
else {m_todo.push_back(expr_pair(arg1, arg2));}
}
if (m_todo.size() > todo_sz) {continue;}
expr_ref u(m);
u = m.mk_app(n1->get_decl(), kids.size(), kids.c_ptr());
m_pinned.push_back(u);
m_cache.insert(n1, n2, u);
}
}
m_g = generalization[m_g];
expr *r;
VERIFY(m_cache.find(e1, e2, r));
res = r;
// create substitutions
s1.reserve(2, m_subs.size());
s2.reserve(2, m_subs.size());
for (unsigned i = 0, sz = m_subs.size(); i < sz; ++i) {
expr_pair p = m_subs.get(i);
s1.insert(i, 0, expr_offset(p.first, 1));
s2.insert(i, 0, expr_offset(p.second, 1));
}
}
@ -318,6 +202,8 @@ public:
*/
bool naive_convex_closure::compute_closure(anti_unifier& au, ast_manager& m,
expr_ref& result) {
NOT_IMPLEMENTED_YET();
#if 0
arith_util util(m);
SASSERT(au.get_num_substitutions() > 0);
@ -411,6 +297,7 @@ bool naive_convex_closure::compute_closure(anti_unifier& au, ast_manager& m,
result = expr_ref(m.mk_exists(vars.size(), sorts.c_ptr(), names.c_ptr(), body),m);
return true;
#endif
}
bool naive_convex_closure::get_range(vector<unsigned int>& v,
@ -453,7 +340,83 @@ void naive_convex_closure::substitute_vars_by_const(ast_manager& m, expr* t,
subs_rw (t, res);
}
/// Construct a pattern by abstracting all numbers by variables
struct mk_num_pat_rewriter : public default_rewriter_cfg {
ast_manager &m;
arith_util m_arith;
// -- mark already seen expressions
ast_mark m_seen;
// -- true if the expression is known to have a number as a sub-expression
ast_mark m_has_num;
// -- expressions created during the transformation
expr_ref_vector m_pinned;
// -- map from introduced variables to expressions they replace
app_ref_vector &m_subs;
// -- stack of expressions being processed to have access to expressions
// -- before rewriting
ptr_buffer<expr> m_stack;
mk_num_pat_rewriter (ast_manager &manager, app_ref_vector& subs) :
m(manager), m_arith(m), m_pinned(m), m_subs(subs) {}
bool pre_visit(expr * t) {
// -- don't touch multiplication
if (m_arith.is_mul(t)) return false;
bool r = (!m_seen.is_marked(t) || m_has_num.is_marked(t));
if (r) {m_stack.push_back (t);}
return r;
}
br_status reduce_app (func_decl * f, unsigned num, expr * const * args,
expr_ref & result, proof_ref & result_pr) {
expr *s;
s = m_stack.back();
m_stack.pop_back();
if (is_app(s)) {
app *a = to_app(s);
for (unsigned i = 0, sz = a->get_num_args(); i < sz; ++i) {
if (m_has_num.is_marked(a->get_arg(i))) {
m_has_num.mark(a, true);
break;
}
}
}
return BR_FAILED;
}
bool cache_all_results() const { return false; }
bool cache_results() const { return false; }
bool get_subst(expr * s, expr * & t, proof * & t_pr) {
if (m_arith.is_numeral(s)) {
t = m.mk_var(m_subs.size(), m.get_sort(s));
m_pinned.push_back(t);
m_subs.push_back(to_app(s));
m_has_num.mark(t, true);
m_seen.mark(t, true);
return true;
}
return false;
}
};
void mk_num_pat(expr *e, expr_ref &result, app_ref_vector &subs) {
SASSERT(subs.empty());
mk_num_pat_rewriter rw_cfg(result.m(), subs);
rewriter_tpl<mk_num_pat_rewriter> rw(result.m(), false, rw_cfg);
rw(e, result);
}
}
template class rewriter_tpl<spacer::var_abs_rewriter>;
template class rewriter_tpl<spacer::subs_rewriter_cfg>;
template class rewriter_tpl<spacer::mk_num_pat_rewriter>;

45
src/muz/spacer/spacer_antiunify.h
View file

@ -22,32 +22,36 @@ Revision History:
#define _SPACER_ANTIUNIFY_H_
#include "ast/ast.h"
#include "ast/substitution/substitution.h"
#include "util/obj_pair_hashtable.h"
namespace spacer {
/**
\brief Anti-unifier for ground expressions
*/
class anti_unifier
{
public:
anti_unifier(expr* t, ast_manager& m);
~anti_unifier() {}
typedef std::pair<expr *, expr *> expr_pair;
typedef pair_hash<obj_ptr_hash<expr>, obj_ptr_hash<expr> > expr_pair_hash;
typedef obj_pair_map<expr, expr, expr*> cache_ty;
bool add_term(expr* t);
void finalize();
expr* get_generalization() {return m_g;}
unsigned get_num_substitutions() {return m_substitutions.size();}
obj_map<expr, expr*> get_substitution(unsigned index){
SASSERT(index < m_substitutions.size());
return m_substitutions[index];
}
private:
ast_manager& m;
// tracking all created expressions
ast_manager &m;
expr_ref_vector m_pinned;
expr_ref m_g;
svector<expr_pair> m_todo;
cache_ty m_cache;
svector<expr_pair> m_subs;
vector<obj_map<expr, expr*>> m_substitutions;
public:
anti_unifier(ast_manager& m);
void reset();
/**
\brief Computes anti-unifier of two ground expressions. Returns
the anti-unifier and the corresponding substitutions
*/
void operator() (expr *e1, expr *e2, expr_ref &res,
substitution &s1, substitution &s2);
};
class naive_convex_closure
@ -63,5 +67,8 @@ private:
expr_ref& res);
};
/// Abstracts numbers in the given ground expression by variables
/// Returns the created pattern and the corresponding substitution.
void mk_num_pat(expr *e, expr_ref &result, app_ref_vector &subs);
}
#endif

38
src/muz/spacer/spacer_callback.cpp Normal file
View file

@ -0,0 +1,38 @@
/**++
Copyright (c) 2017 Microsoft Corporation and Matteo Marescotti
Module Name:
spacer_callback.cpp
Abstract:
SPACER plugin for handling events
Author:
Matteo Marescotti
Notes:
--*/
#include "spacer_callback.h"
#include "muz/spacer/spacer_context.h"
namespace spacer {
void user_callback::new_lemma_eh(expr *lemma, unsigned level) {
m_new_lemma_eh(m_state, lemma, level);
}
void user_callback::predecessor_eh() {
m_predecessor_eh(m_state);
}
void user_callback::unfold_eh() {
m_unfold_eh(m_state);
}
}

65
src/muz/spacer/spacer_callback.h Normal file
View file

@ -0,0 +1,65 @@
/**++
Copyright (c) 2017 Microsoft Corporation and Matteo Marescotti
Module Name:
spacer_callback.h
Abstract:
SPACER plugin for handling events
Author:
Matteo Marescotti
Notes:
--*/
#ifndef _SPACER_CALLBACK_H_
#define _SPACER_CALLBACK_H_
#include "muz/spacer/spacer_context.h"
#include "muz/base/dl_engine_base.h"
namespace spacer {
class user_callback : public spacer_callback {
private:
void *m_state;
const datalog::t_new_lemma_eh m_new_lemma_eh;
const datalog::t_predecessor_eh m_predecessor_eh;
const datalog::t_unfold_eh m_unfold_eh;
public:
user_callback(context &context,
void *state,
const datalog::t_new_lemma_eh new_lemma_eh,
const datalog::t_predecessor_eh predecessor_eh,
const datalog::t_unfold_eh unfold_eh) :
spacer_callback(context),
m_state(state),
m_new_lemma_eh(new_lemma_eh),
m_predecessor_eh(predecessor_eh),
m_unfold_eh(unfold_eh) {}
inline bool new_lemma() override { return m_new_lemma_eh != nullptr; }
void new_lemma_eh(expr *lemma, unsigned level) override;
inline bool predecessor() override { return m_predecessor_eh != nullptr; }
void predecessor_eh() override;
inline bool unfold() override { return m_unfold_eh != nullptr; }
void unfold_eh() override;
};
}
#endif //_SPACER_CALLBACK_H_

3045
src/muz/spacer/spacer_context.cpp
View file

File diff suppressed because it is too large Load diff

685
src/muz/spacer/spacer_context.h
View file

File diff suppressed because it is too large Load diff

29
src/muz/spacer/spacer_dl_interface.cpp
View file

@ -34,6 +34,7 @@ Revision History:
#include "model/model_smt2_pp.h"
#include "ast/scoped_proof.h"
#include "muz/transforms/dl_transforms.h"
#include "muz/spacer/spacer_callback.h"
using namespace spacer;
@ -92,19 +93,14 @@ lbool dl_interface::query(expr * query)
datalog::rule_set old_rules(rules0);
func_decl_ref query_pred(m);
rm.mk_query(query, m_ctx.get_rules());
expr_ref bg_assertion = m_ctx.get_background_assertion();
check_reset();
TRACE("spacer",
if (!m.is_true(bg_assertion)) {
tout << "axioms:\n";
tout << mk_pp(bg_assertion, m) << "\n";
}
tout << "query: " << mk_pp(query, m) << "\n";
tout << "rules:\n";
m_ctx.display_rules(tout);
);
tout << "query: " << mk_pp(query, m) << "\n";
tout << "rules:\n";
m_ctx.display_rules(tout);
);
apply_default_transformation(m_ctx);
@ -160,7 +156,6 @@ lbool dl_interface::query(expr * query)
m_context->set_proof_converter(m_ctx.get_proof_converter());
m_context->set_model_converter(m_ctx.get_model_converter());
m_context->set_query(query_pred);
m_context->set_axioms(bg_assertion);
m_context->update_rules(m_spacer_rules);
if (m_spacer_rules.get_rules().empty()) {
@ -169,7 +164,7 @@ lbool dl_interface::query(expr * query)
return l_false;
}
return m_context->solve();
return m_context->solve(m_ctx.get_params().spacer_min_level());
}
@ -254,7 +249,6 @@ lbool dl_interface::query_from_lvl(expr * query, unsigned lvl)
m_context->set_proof_converter(m_ctx.get_proof_converter());
m_context->set_model_converter(m_ctx.get_model_converter());
m_context->set_query(query_pred);
m_context->set_axioms(bg_assertion);
m_context->update_rules(m_spacer_rules);
if (m_spacer_rules.get_rules().empty()) {
@ -352,3 +346,14 @@ proof_ref dl_interface::get_proof()
{
return m_context->get_proof();
}
void dl_interface::add_callback(void *state,
const datalog::t_new_lemma_eh new_lemma_eh,
const datalog::t_predecessor_eh predecessor_eh,
const datalog::t_unfold_eh unfold_eh){
m_context->callbacks().push_back(alloc(user_callback, *m_context, state, new_lemma_eh, predecessor_eh, unfold_eh));
}
void dl_interface::add_constraint (expr *c, unsigned lvl){
m_context->add_constraint(c, lvl);
}

7
src/muz/spacer/spacer_dl_interface.h
View file

@ -79,6 +79,13 @@ public:
proof_ref get_proof() override;
void add_callback(void *state,
const datalog::t_new_lemma_eh new_lemma_eh,
const datalog::t_predecessor_eh predecessor_eh,
const datalog::t_unfold_eh unfold_eh) override;
void add_constraint (expr *c, unsigned lvl) override;
};
}

6
src/muz/spacer/spacer_farkas_learner.h
View file

@ -24,12 +24,6 @@ Revision History:
namespace spacer {
class farkas_learner {
typedef obj_hashtable<expr> expr_set;

185
src/muz/spacer/spacer_generalizers.cpp
View file

@ -21,11 +21,16 @@ Revision History:
#include "muz/spacer/spacer_context.h"
#include "muz/spacer/spacer_generalizers.h"
#include "ast/ast_util.h"
#include "ast/expr_abstract.h"
#include "ast/rewriter/var_subst.h"
#include "ast/for_each_expr.h"
#include "ast/factor_equivs.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/substitution/matcher.h"
#include "ast/expr_functors.h"
#include "smt/smt_solver.h"
#include "qe/qe_term_graph.h"
namespace spacer {
void lemma_sanity_checker::operator()(lemma_ref &lemma) {
@ -33,9 +38,23 @@ void lemma_sanity_checker::operator()(lemma_ref &lemma) {
expr_ref_vector cube(lemma->get_ast_manager());
cube.append(lemma->get_cube());
ENSURE(lemma->get_pob()->pt().check_inductive(lemma->level(),
cube, uses_level));
cube, uses_level,
lemma->weakness()));
}
namespace{
class contains_array_op_proc : public i_expr_pred {
ast_manager &m;
family_id m_array_fid;
public:
contains_array_op_proc(ast_manager &manager) :
m(manager), m_array_fid(m.mk_family_id("array"))
{}
virtual bool operator()(expr *e) {
return is_app(e) && to_app(e)->get_family_id() == m_array_fid;
}
};
}
// ------------------------
// lemma_bool_inductive_generalizer
@ -50,6 +69,9 @@ void lemma_bool_inductive_generalizer::operator()(lemma_ref &lemma) {
pred_transformer &pt = lemma->get_pob()->pt();
ast_manager &m = pt.get_ast_manager();
contains_array_op_proc has_array_op(m);
check_pred has_arrays(has_array_op, m);
expr_ref_vector cube(m);
cube.append(lemma->get_cube());
@ -58,14 +80,21 @@ void lemma_bool_inductive_generalizer::operator()(lemma_ref &lemma) {
ptr_vector<expr> processed;
expr_ref_vector extra_lits(m);
unsigned weakness = lemma->weakness();
unsigned i = 0, num_failures = 0;
while (i < cube.size() &&
(!m_failure_limit || num_failures < m_failure_limit)) {
expr_ref lit(m);
lit = cube.get(i);
if (m_array_only && !has_arrays(lit)) {
processed.push_back(lit);
++i;
continue;
}
cube[i] = true_expr;
if (cube.size() > 1 &&
pt.check_inductive(lemma->level(), cube, uses_level)) {
pt.check_inductive(lemma->level(), cube, uses_level, weakness)) {
num_failures = 0;
dirty = true;
for (i = 0; i < cube.size() &&
@ -82,7 +111,7 @@ void lemma_bool_inductive_generalizer::operator()(lemma_ref &lemma) {
SASSERT(extra_lits.size() > 1);
for (unsigned j = 0, sz = extra_lits.size(); !found && j < sz; ++j) {
cube[i] = extra_lits.get(j);
if (pt.check_inductive(lemma->level(), cube, uses_level)) {
if (pt.check_inductive(lemma->level(), cube, uses_level, weakness)) {
num_failures = 0;
dirty = true;
found = true;
@ -130,10 +159,11 @@ void unsat_core_generalizer::operator()(lemma_ref &lemma)
unsigned old_sz = lemma->get_cube().size();
unsigned old_level = lemma->level();
(void)old_level;
unsigned uses_level;
expr_ref_vector core(m);
VERIFY(pt.is_invariant(old_level, lemma->get_expr(), uses_level, &core));
VERIFY(pt.is_invariant(lemma->level(), lemma.get(), uses_level, &core));
CTRACE("spacer", old_sz > core.size(),
tout << "unsat core reduced lemma from: "
@ -176,118 +206,131 @@ public:
};
}
bool lemma_array_eq_generalizer::is_array_eq (ast_manager &m, expr* e) {
expr *e1 = nullptr, *e2 = nullptr;
if (m.is_eq(e, e1, e2) && is_app(e1) && is_app(e2)) {
app *a1 = to_app(e1);
app *a2 = to_app(e2);
array_util au(m);
if (a1->get_family_id() == null_family_id &&
a2->get_family_id() == null_family_id &&
au.is_array(a1) && au.is_array(a2))
return true;
}
return false;
}
void lemma_array_eq_generalizer::operator() (lemma_ref &lemma)
{
TRACE("core_array_eq", tout << "Looking for equalities\n";);
// -- find array constants
ast_manager &m = lemma->get_ast_manager();
manager &pm = m_ctx.get_manager();
(void)pm;
expr_ref_vector core(m);
expr_ref v(m);
func_decl_set symb;
collect_array_proc cap(m, symb);
// -- find array constants
core.append (lemma->get_cube());
v = mk_and(core);
for_each_expr(cap, v);
TRACE("core_array_eq",
CTRACE("core_array_eq", symb.size() > 1 && symb.size() <= 8,
tout << "found " << symb.size() << " array variables in: \n"
<< mk_pp(v, m) << "\n";);
<< v << "\n";);
// too few constants
if (symb.size() <= 1) { return; }
// too many constants, skip this
if (symb.size() >= 8) { return; }
// too few constants or too many constants
if (symb.size() <= 1 || symb.size() > 8) { return; }
// -- for every pair of variables, try an equality
typedef func_decl_set::iterator iterator;
// -- for every pair of constants (A, B), check whether the
// -- equality (A=B) generalizes a literal in the lemma
ptr_vector<func_decl> vsymbs;
for (iterator it = symb.begin(), end = symb.end();
it != end; ++it)
{ vsymbs.push_back(*it); }
for (auto * fdecl : symb) {vsymbs.push_back(fdecl);}
// create all equalities
expr_ref_vector eqs(m);
for (unsigned i = 0, sz = vsymbs.size(); i < sz; ++i) {
for (unsigned j = i + 1; j < sz; ++j) {
eqs.push_back(m.mk_eq(m.mk_const(vsymbs.get(i)),
m.mk_const(vsymbs.get(j))));
}
}
for (unsigned i = 0, sz = vsymbs.size(); i < sz; ++i)
for (unsigned j = i + 1; j < sz; ++j)
{ eqs.push_back(m.mk_eq(m.mk_const(vsymbs.get(i)),
m.mk_const(vsymbs.get(j)))); }
smt::kernel solver(m, m_ctx.get_manager().fparams2());
// smt-solver to check whether a literal is generalized. using
// default params. There has to be a simpler way to approximate
// this check
ref<solver> sol = mk_smt_solver(m, params_ref::get_empty(), symbol::null);
// literals of the new lemma
expr_ref_vector lits(m);
for (unsigned i = 0, core_sz = core.size(); i < core_sz; ++i) {
SASSERT(lits.size() == i);
solver.push();
solver.assert_expr(core.get(i));
for (unsigned j = 0, eqs_sz = eqs.size(); j < eqs_sz; ++j) {
solver.push();
solver.assert_expr(eqs.get(j));
lbool res = solver.check();
solver.pop(1);
lits.append(core);
expr *t = nullptr;
bool dirty = false;
for (unsigned i = 0, sz = core.size(); i < sz; ++i) {
// skip a literal is it is already an array equality
if (m.is_not(lits.get(i), t) && is_array_eq(m, t)) continue;
solver::scoped_push _pp_(*sol);
sol->assert_expr(lits.get(i));
for (auto *e : eqs) {
solver::scoped_push _p_(*sol);
sol->assert_expr(e);
lbool res = sol->check_sat(0, nullptr);
if (res == l_false) {
TRACE("core_array_eq",
tout << "strengthened " << mk_pp(core.get(i), m)
<< " with " << mk_pp(m.mk_not(eqs.get(j)), m) << "\n";);
lits.push_back(m.mk_not(eqs.get(j)));
tout << "strengthened " << mk_pp(lits.get(i), m)
<< " with " << mk_pp(mk_not(m, e), m) << "\n";);
lits[i] = mk_not(m, e);
dirty = true;
break;
}
}
solver.pop(1);
if (lits.size() == i) { lits.push_back(core.get(i)); }
}
/**
HACK: if the first 3 arguments of pt are boolean, assume
they correspond to SeaHorn encoding and condition the equality on them.
*/
// pred_transformer &pt = n.pt ();
// if (pt.sig_size () >= 3 &&
// m.is_bool (pt.sig (0)->get_range ()) &&
// m.is_bool (pt.sig (1)->get_range ()) &&
// m.is_bool (pt.sig (2)->get_range ()))
// {
// lits.push_back (m.mk_const (pm.o2n(pt.sig (0), 0)));
// lits.push_back (m.mk_not (m.mk_const (pm.o2n(pt.sig (1), 0))));
// lits.push_back (m.mk_not (m.mk_const (pm.o2n(pt.sig (2), 0))));
// }
// nothing changed
if (!dirty) return;
TRACE("core_array_eq", tout << "new possible core "
<< mk_pp(pm.mk_and(lits), m) << "\n";);
TRACE("core_array_eq",
tout << "new possible core " << mk_and(lits) << "\n";);
pred_transformer &pt = lemma->get_pob()->pt();
// -- check if it is consistent with the transition relation
// -- check if the generalized result is consistent with trans
unsigned uses_level1;
if (pt.check_inductive(lemma->level(), lits, uses_level1)) {
if (pt.check_inductive(lemma->level(), lits, uses_level1, lemma->weakness())) {
TRACE("core_array_eq", tout << "Inductive!\n";);
lemma->update_cube(lemma->get_pob(),lits);
lemma->update_cube(lemma->get_pob(), lits);
lemma->set_level(uses_level1);
return;
} else
{ TRACE("core_array_eq", tout << "Not-Inductive!\n";);}
}
else
{TRACE("core_array_eq", tout << "Not-Inductive!\n";);}
}
void lemma_eq_generalizer::operator() (lemma_ref &lemma)
{
TRACE("core_eq", tout << "Transforming equivalence classes\n";);
ast_manager &m = m_ctx.get_ast_manager();
expr_ref_vector core(m);
core.append (lemma->get_cube());
if (lemma->get_cube().empty()) return;
bool dirty;
expr_equiv_class eq_classes(m);
factor_eqs(core, eq_classes);
// create all possible equalities to allow for simple inductive generalization
dirty = equiv_to_expr_full(eq_classes, core);
if (dirty) {
ast_manager &m = m_ctx.get_ast_manager();
qe::term_graph egraph(m);
egraph.add_lits(lemma->get_cube());
// -- expand the cube with all derived equalities
expr_ref_vector core(m);
egraph.to_lits(core, true);
// -- if the core looks different from the original cube
if (core.size() != lemma->get_cube().size() ||
core.get(0) != lemma->get_cube().get(0)) {
// -- update the lemma
lemma->update_cube(lemma->get_pob(), core);
}
}
};

48
src/muz/spacer/spacer_generalizers.h
View file

@ -48,11 +48,14 @@ class lemma_bool_inductive_generalizer : public lemma_generalizer {
};
unsigned m_failure_limit;
bool m_array_only;
stats m_st;
public:
lemma_bool_inductive_generalizer(context& ctx, unsigned failure_limit) :
lemma_generalizer(ctx), m_failure_limit(failure_limit) {}
lemma_bool_inductive_generalizer(context& ctx, unsigned failure_limit,
bool array_only = false) :
lemma_generalizer(ctx), m_failure_limit(failure_limit),
m_array_only(array_only) {}
~lemma_bool_inductive_generalizer() override {}
void operator()(lemma_ref &lemma) override;
@ -80,6 +83,8 @@ public:
};
class lemma_array_eq_generalizer : public lemma_generalizer {
private:
bool is_array_eq(ast_manager &m, expr *e);
public:
lemma_array_eq_generalizer(context &ctx) : lemma_generalizer(ctx) {}
~lemma_array_eq_generalizer() override {}
@ -94,6 +99,45 @@ public:
void operator()(lemma_ref &lemma) override;
};
class lemma_quantifier_generalizer : public lemma_generalizer {
struct stats {
unsigned count;
unsigned num_failures;
stopwatch watch;
stats() {reset();}
void reset() {count = 0; num_failures = 0; watch.reset();}
};
ast_manager &m;
arith_util m_arith;
stats m_st;
expr_ref_vector m_cube;
bool m_normalize_cube;
int m_offset;
public:
lemma_quantifier_generalizer(context &ctx, bool normalize_cube = true);
virtual ~lemma_quantifier_generalizer() {}
virtual void operator()(lemma_ref &lemma);
virtual void collect_statistics(statistics& st) const;
virtual void reset_statistics() {m_st.reset();}
private:
bool generalize(lemma_ref &lemma, app *term);
void find_candidates(expr *e, app_ref_vector &candidate);
bool is_ub(var *var, expr *e);
bool is_lb(var *var, expr *e);
void mk_abs_cube (lemma_ref &lemma, app *term, var *var,
expr_ref_vector &gnd_cube,
expr_ref_vector &abs_cube,
expr *&lb, expr *&ub, unsigned &stride);
bool match_sk_idx(expr *e, app_ref_vector const &zks, expr *&idx, app *&sk);
void cleanup(expr_ref_vector& cube, app_ref_vector const &zks, expr_ref &bind);
bool find_stride(expr_ref_vector &c, expr_ref &pattern, unsigned &stride);
};
}
#endif

355
src/muz/spacer/spacer_itp_solver.cpp
View file

@ -1,355 +0,0 @@
/**
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_itp_solver.cpp
Abstract:
A solver that produces interpolated unsat cores
Author:
Arie Gurfinkel
Notes:
--*/
#include"muz/spacer/spacer_itp_solver.h"
#include"ast/ast.h"
#include"muz/spacer/spacer_util.h"
#include"muz/spacer/spacer_farkas_learner.h"
#include"ast/rewriter/expr_replacer.h"
#include"muz/spacer/spacer_unsat_core_learner.h"
#include"muz/spacer/spacer_unsat_core_plugin.h"
namespace spacer {
void itp_solver::push ()
{
m_defs.push_back (def_manager (*this));
m_solver.push ();
}
void itp_solver::pop (unsigned n)
{
m_solver.pop (n);
unsigned lvl = m_defs.size ();
SASSERT (n <= lvl);
unsigned new_lvl = lvl-n;
while (m_defs.size() > new_lvl) {
m_num_proxies -= m_defs.back ().m_defs.size ();
m_defs.pop_back ();
}
}
app* itp_solver::fresh_proxy ()
{
if (m_num_proxies == m_proxies.size()) {
std::stringstream name;
name << "spacer_proxy!" << m_proxies.size ();
app_ref res(m);
res = m.mk_const (symbol (name.str ().c_str ()),
m.mk_bool_sort ());
m_proxies.push_back (res);
// -- add the new proxy to proxy eliminator
proof_ref pr(m);
pr = m.mk_asserted (m.mk_true ());
m_elim_proxies_sub.insert (res, m.mk_true (), pr);
}
return m_proxies.get (m_num_proxies++);
}
app* itp_solver::mk_proxy (expr *v)
{
{
expr *e = v;
m.is_not (v, e);
if (is_uninterp_const(e)) { return to_app(v); }
}
def_manager &def = m_defs.size () > 0 ? m_defs.back () : m_base_defs;
return def.mk_proxy (v);
}
bool itp_solver::mk_proxies (expr_ref_vector &v, unsigned from)
{
bool dirty = false;
for (unsigned i = from, sz = v.size(); i < sz; ++i) {
app *p = mk_proxy (v.get (i));
dirty |= (v.get (i) != p);
v[i] = p;
}
return dirty;
}
void itp_solver::push_bg (expr *e)
{
if (m_assumptions.size () > m_first_assumption)
{ m_assumptions.shrink(m_first_assumption); }
m_assumptions.push_back (e);
m_first_assumption = m_assumptions.size ();
}
void itp_solver::pop_bg (unsigned n)
{
if (n == 0) { return; }
if (m_assumptions.size () > m_first_assumption)
{ m_assumptions.shrink(m_first_assumption); }
m_first_assumption = m_first_assumption > n ? m_first_assumption - n : 0;
m_assumptions.shrink (m_first_assumption);
}
unsigned itp_solver::get_num_bg () {return m_first_assumption;}
lbool itp_solver::check_sat (unsigned num_assumptions, expr * const *assumptions)
{
// -- remove any old assumptions
if (m_assumptions.size () > m_first_assumption)
{ m_assumptions.shrink(m_first_assumption); }
// -- replace theory literals in background assumptions with proxies
mk_proxies (m_assumptions);
// -- in case mk_proxies added new literals, they are all background
m_first_assumption = m_assumptions.size ();
m_assumptions.append (num_assumptions, assumptions);
m_is_proxied = mk_proxies (m_assumptions, m_first_assumption);
lbool res;
res = m_solver.check_sat (m_assumptions.size (), m_assumptions.c_ptr ());
set_status (res);
return res;
}
app* itp_solver::def_manager::mk_proxy (expr *v)
{
app* r;
if (m_expr2proxy.find(v, r)) { return r; }
ast_manager &m = m_parent.m;
app_ref proxy(m);
app_ref def(m);
proxy = m_parent.fresh_proxy ();
def = m.mk_or (m.mk_not (proxy), v);
m_defs.push_back (def);
m_expr2proxy.insert (v, proxy);
m_proxy2def.insert (proxy, def);
m_parent.assert_expr (def.get ());
return proxy;
}
bool itp_solver::def_manager::is_proxy (app *k, app_ref &def)
{
app *r = nullptr;
bool found = m_proxy2def.find (k, r);
def = r;
return found;
}
void itp_solver::def_manager::reset ()
{
m_expr2proxy.reset ();
m_proxy2def.reset ();
m_defs.reset ();
}
bool itp_solver::def_manager::is_proxy_def (expr *v)
{
// XXX This might not be the most robust way to check
return m_defs.contains (v);
}
bool itp_solver::is_proxy(expr *e, app_ref &def)
{
if (!is_uninterp_const(e)) { return false; }
app *a = to_app (e);
for (int i = m_defs.size (); i > 0; --i)
if (m_defs[i-1].is_proxy (a, def))
{ return true; }
if (m_base_defs.is_proxy (a, def))
{ return true; }
return false;
}
void itp_solver::collect_statistics (statistics &st) const
{
m_solver.collect_statistics (st);
st.update ("time.itp_solver.itp_core", m_itp_watch.get_seconds ());
}
void itp_solver::reset_statistics ()
{
m_itp_watch.reset ();
}
void itp_solver::get_unsat_core (ptr_vector<expr> &core)
{
m_solver.get_unsat_core (core);
undo_proxies_in_core (core);
}
void itp_solver::undo_proxies_in_core (ptr_vector<expr> &r)
{
app_ref e(m);
expr_fast_mark1 bg;
for (unsigned i = 0; i < m_first_assumption; ++i)
{ bg.mark(m_assumptions.get(i)); }
// expand proxies
unsigned j = 0;
for (unsigned i = 0, sz = r.size(); i < sz; ++i) {
// skip background assumptions
if (bg.is_marked(r[i])) { continue; }
// -- undo proxies, but only if they were introduced in check_sat
if (m_is_proxied && is_proxy(r[i], e)) {
SASSERT (m.is_or (e));
r[j] = e->get_arg (1);
} else if (i != j) { r[j] = r[i]; }
j++;
}
r.shrink (j);
}
void itp_solver::undo_proxies (expr_ref_vector &r)
{
app_ref e(m);
// expand proxies
for (unsigned i = 0, sz = r.size (); i < sz; ++i)
if (is_proxy(r.get(i), e)) {
SASSERT (m.is_or (e));
r[i] = e->get_arg (1);
}
}
void itp_solver::get_unsat_core (expr_ref_vector &_core)
{
ptr_vector<expr> core;
get_unsat_core (core);
_core.append (core.size (), core.c_ptr ());
}
void itp_solver::elim_proxies (expr_ref_vector &v)
{
expr_ref f = mk_and (v);
scoped_ptr<expr_replacer> rep = mk_expr_simp_replacer (m);
rep->set_substitution (&m_elim_proxies_sub);
(*rep) (f);
v.reset ();
flatten_and (f, v);
}
void itp_solver::get_itp_core (expr_ref_vector &core)
{
scoped_watch _t_ (m_itp_watch);
typedef obj_hashtable<expr> expr_set;
expr_set B;
for (unsigned i = m_first_assumption, sz = m_assumptions.size(); i < sz; ++i) {
expr *a = m_assumptions.get (i);
app_ref def(m);
if (is_proxy(a, def)) { B.insert(def.get()); }
B.insert (a);
}
proof_ref pr(m);
pr = get_proof ();
if (!m_new_unsat_core) {
// old code
farkas_learner learner_old;
learner_old.set_split_literals(m_split_literals);
learner_old.get_lemmas (pr, B, core);
elim_proxies (core);
simplify_bounds (core); // XXX potentially redundant
} else {
// new code
unsat_core_learner learner(m);
if (m_farkas_optimized) {
if (true) // TODO: proper options
{
unsat_core_plugin_farkas_lemma_optimized* plugin_farkas_lemma_optimized = alloc(unsat_core_plugin_farkas_lemma_optimized, learner,m);
learner.register_plugin(plugin_farkas_lemma_optimized);
}
else
{
unsat_core_plugin_farkas_lemma_bounded* plugin_farkas_lemma_bounded = alloc(unsat_core_plugin_farkas_lemma_bounded, learner,m);
learner.register_plugin(plugin_farkas_lemma_bounded);
}
} else {
unsat_core_plugin_farkas_lemma* plugin_farkas_lemma = alloc(unsat_core_plugin_farkas_lemma, learner, m_split_literals, m_farkas_a_const);
learner.register_plugin(plugin_farkas_lemma);
}
if (m_minimize_unsat_core) {
unsat_core_plugin_min_cut* plugin_min_cut = alloc(unsat_core_plugin_min_cut, learner, m);
learner.register_plugin(plugin_min_cut);
} else {
unsat_core_plugin_lemma* plugin_lemma = alloc(unsat_core_plugin_lemma, learner);
learner.register_plugin(plugin_lemma);
}
learner.compute_unsat_core(pr, B, core);
elim_proxies (core);
simplify_bounds (core); // XXX potentially redundant
// // debug
// expr_ref_vector core2(m);
// unsat_core_learner learner2(m);
//
// unsat_core_plugin_farkas_lemma* plugin_farkas_lemma2 = alloc(unsat_core_plugin_farkas_lemma, learner2, m_split_literals);
// learner2.register_plugin(plugin_farkas_lemma2);
// unsat_core_plugin_lemma* plugin_lemma2 = alloc(unsat_core_plugin_lemma, learner2);
// learner2.register_plugin(plugin_lemma2);
// learner2.compute_unsat_core(pr, B, core2);
//
// elim_proxies (core2);
// simplify_bounds (core2);
//
// IF_VERBOSE(2,
// verbose_stream () << "Itp Core:\n"
// << mk_pp (mk_and (core), m) << "\n";);
// IF_VERBOSE(2,
// verbose_stream () << "Itp Core2:\n"
// << mk_pp (mk_and (core2), m) << "\n";);
//SASSERT(mk_and (core) == mk_and (core2));
}
IF_VERBOSE(2,
verbose_stream () << "Itp Core:\n"
<< mk_pp (mk_and (core), m) << "\n";);
}
void itp_solver::refresh ()
{
// only refresh in non-pushed state
SASSERT (m_defs.size () == 0);
expr_ref_vector assertions (m);
for (unsigned i = 0, e = m_solver.get_num_assertions(); i < e; ++i) {
expr* a = m_solver.get_assertion (i);
if (!m_base_defs.is_proxy_def(a)) { assertions.push_back(a); }
}
m_base_defs.reset ();
NOT_IMPLEMENTED_YET ();
// solver interface does not have a reset method. need to introduce it somewhere.
// m_solver.reset ();
for (unsigned i = 0, e = assertions.size (); i < e; ++i)
{ m_solver.assert_expr(assertions.get(i)); }
}
}

172
src/muz/spacer/spacer_itp_solver.h
View file

@ -1,172 +0,0 @@
/**
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_itp_solver.h
Abstract:
A solver that produces interpolated unsat cores
Author:
Arie Gurfinkel
Notes:
--*/
#ifndef SPACER_ITP_SOLVER_H_
#define SPACER_ITP_SOLVER_H_
#include"solver/solver.h"
#include"ast/expr_substitution.h"
#include"util/stopwatch.h"
namespace spacer {
class itp_solver : public solver {
private:
struct def_manager {
itp_solver &m_parent;
obj_map<expr, app*> m_expr2proxy;
obj_map<app, app*> m_proxy2def;
expr_ref_vector m_defs;
def_manager(itp_solver &parent) :
m_parent(parent), m_defs(m_parent.m)
{}
bool is_proxy(app *k, app_ref &v);
app* mk_proxy(expr *v);
void reset();
bool is_proxy_def(expr *v);
};
friend struct def_manager;
ast_manager &m;
solver &m_solver;
app_ref_vector m_proxies;
unsigned m_num_proxies;
vector<def_manager> m_defs;
def_manager m_base_defs;
expr_ref_vector m_assumptions;
unsigned m_first_assumption;
bool m_is_proxied;
stopwatch m_itp_watch;
expr_substitution m_elim_proxies_sub;
bool m_split_literals;
bool m_new_unsat_core;
bool m_minimize_unsat_core;
bool m_farkas_optimized;
bool m_farkas_a_const;
bool is_proxy(expr *e, app_ref &def);
void undo_proxies_in_core(ptr_vector<expr> &v);
app* mk_proxy(expr *v);
app* fresh_proxy();
void elim_proxies(expr_ref_vector &v);
public:
itp_solver(solver &solver, bool new_unsat_core, bool minimize_unsat_core, bool farkas_optimized, bool farkas_a_const, bool split_literals = false) :
m(solver.get_manager()),
m_solver(solver),
m_proxies(m),
m_num_proxies(0),
m_base_defs(*this),
m_assumptions(m),
m_first_assumption(0),
m_is_proxied(false),
m_elim_proxies_sub(m, false, true),
m_split_literals(split_literals),
m_new_unsat_core(new_unsat_core),
m_minimize_unsat_core(minimize_unsat_core),
m_farkas_optimized(farkas_optimized),
m_farkas_a_const(farkas_a_const)
{}
~itp_solver() override {}
/* itp solver specific */
void get_unsat_core(expr_ref_vector &core) override;
virtual void get_itp_core(expr_ref_vector &core);
void set_split_literals(bool v) {m_split_literals = v;}
bool mk_proxies(expr_ref_vector &v, unsigned from = 0);
void undo_proxies(expr_ref_vector &v);
void push_bg(expr *e);
void pop_bg(unsigned n);
unsigned get_num_bg();
void get_full_unsat_core(ptr_vector<expr> &core)
{m_solver.get_unsat_core(core);}
/* solver interface */
solver* translate(ast_manager &m, params_ref const &p) override { return m_solver.translate(m, p);}
void updt_params(params_ref const &p) override { m_solver.updt_params(p);}
void collect_param_descrs(param_descrs &r) override { m_solver.collect_param_descrs(r);}
void set_produce_models(bool f) override { m_solver.set_produce_models(f);}
void assert_expr_core(expr *t) override { m_solver.assert_expr(t);}
void assert_expr_core2(expr *t, expr *a) override { NOT_IMPLEMENTED_YET();}
expr_ref_vector cube(expr_ref_vector&, unsigned) override { return expr_ref_vector(m); }
void push() override;
void pop(unsigned n) override;
unsigned get_scope_level() const override
{return m_solver.get_scope_level();}
lbool check_sat(unsigned num_assumptions, expr * const *assumptions) override;
void set_progress_callback(progress_callback *callback) override
{m_solver.set_progress_callback(callback);}
unsigned get_num_assertions() const override
{return m_solver.get_num_assertions();}
expr * get_assertion(unsigned idx) const override
{return m_solver.get_assertion(idx);}
unsigned get_num_assumptions() const override
{return m_solver.get_num_assumptions();}
expr * get_assumption(unsigned idx) const override
{return m_solver.get_assumption(idx);}
std::ostream &display(std::ostream &out, unsigned n, expr* const* es) const override
{ return m_solver.display(out, n, es); }
/* check_sat_result interface */
void collect_statistics(statistics &st) const override ;
virtual void reset_statistics();
void get_unsat_core(ptr_vector<expr> &r) override;
void get_model_core(model_ref &m) override {m_solver.get_model(m);}
proof *get_proof() override {return m_solver.get_proof();}
std::string reason_unknown() const override
{return m_solver.reason_unknown();}
void set_reason_unknown(char const* msg) override
{m_solver.set_reason_unknown(msg);}
void get_labels(svector<symbol> &r) override
{m_solver.get_labels(r);}
ast_manager &get_manager() const override {return m;}
virtual void refresh();
class scoped_mk_proxy {
itp_solver &m_s;
expr_ref_vector &m_v;
public:
scoped_mk_proxy(itp_solver &s, expr_ref_vector &v) : m_s(s), m_v(v)
{m_s.mk_proxies(m_v);}
~scoped_mk_proxy()
{m_s.undo_proxies(m_v);}
};
class scoped_bg {
itp_solver &m_s;
unsigned m_bg_sz;
public:
scoped_bg(itp_solver &s) : m_s(s), m_bg_sz(m_s.get_num_bg()) {}
~scoped_bg()
{if (m_s.get_num_bg() > m_bg_sz) { m_s.pop_bg(m_s.get_num_bg() - m_bg_sz); }}
};
};
}
#endif

280
src/muz/spacer/spacer_iuc_proof.cpp Normal file
View file

@ -0,0 +1,280 @@
#include <unordered_map>
#include "ast/ast_pp_dot.h"
#include "muz/spacer/spacer_iuc_proof.h"
#include "ast/for_each_expr.h"
#include "ast/array_decl_plugin.h"
#include "ast/proofs/proof_utils.h"
#include "muz/spacer/spacer_proof_utils.h"
#include "muz/spacer/spacer_util.h"
namespace spacer {
/*
* ====================================
* init
* ====================================
*/
iuc_proof::iuc_proof(ast_manager& m, proof* pr, const expr_set& core_lits) :
m(m), m_pr(pr,m) {
for (auto lit : core_lits) m_core_lits.insert(lit);
// init A-marks and B-marks
collect_core_symbols();
compute_marks();
}
iuc_proof::iuc_proof(ast_manager& m, proof* pr, const expr_ref_vector& core_lits) :
m(m), m_pr(pr,m) {
for (auto lit : core_lits) m_core_lits.insert(lit);
// init A-marks and B-marks
collect_core_symbols();
compute_marks();
}
/*
* ====================================
* methods for computing symbol colors
* ====================================
*/
class collect_pure_proc {
func_decl_set& m_symbs;
public:
collect_pure_proc(func_decl_set& s):m_symbs(s) {}
void operator()(app* a) {
if (a->get_family_id() == null_family_id) {
m_symbs.insert(a->get_decl());
}
}
void operator()(var*) {}
void operator()(quantifier*) {}
};
void iuc_proof::collect_core_symbols()
{
expr_mark visited;
collect_pure_proc proc(m_core_symbols);
for (auto lit : m_core_lits)
for_each_expr(proc, visited, lit);
}
class is_pure_expr_proc {
func_decl_set const& m_symbs;
array_util m_au;
public:
struct non_pure {};
is_pure_expr_proc(func_decl_set const& s, ast_manager& m):
m_symbs(s),
m_au (m)
{}
void operator()(app* a) {
if (a->get_family_id() == null_family_id) {
if (!m_symbs.contains(a->get_decl())) {
throw non_pure();
}
}
else if (a->get_family_id () == m_au.get_family_id () &&
a->is_app_of (a->get_family_id (), OP_ARRAY_EXT)) {
throw non_pure();
}
}
void operator()(var*) {}
void operator()(quantifier*) {}
};
bool iuc_proof::is_core_pure(expr* e) const
{
is_pure_expr_proc proc(m_core_symbols, m);
try {
for_each_expr(proc, e);
}
catch (is_pure_expr_proc::non_pure)
{return false;}
return true;
}
void iuc_proof::compute_marks()
{
proof_post_order it(m_pr, m);
while (it.hasNext())
{
proof* cur = it.next();
if (m.get_num_parents(cur) == 0)
{
switch(cur->get_decl_kind())
{
case PR_ASSERTED:
if (m_core_lits.contains(m.get_fact(cur)))
m_b_mark.mark(cur, true);
else
m_a_mark.mark(cur, true);
break;
case PR_HYPOTHESIS:
m_h_mark.mark(cur, true);
break;
default:
break;
}
}
else
{
// collect from parents whether derivation of current node
// contains A-axioms, B-axioms and hypothesis
bool need_to_mark_a = false;
bool need_to_mark_b = false;
bool need_to_mark_h = false;
for (unsigned i = 0; i < m.get_num_parents(cur); ++i)
{
SASSERT(m.is_proof(cur->get_arg(i)));
proof* premise = to_app(cur->get_arg(i));
need_to_mark_a |= m_a_mark.is_marked(premise);
need_to_mark_b |= m_b_mark.is_marked(premise);
need_to_mark_h |= m_h_mark.is_marked(premise);
}
// if current node is application of a lemma, then all
// active hypotheses are removed
if(cur->get_decl_kind() == PR_LEMMA) need_to_mark_h = false;
// save results
m_a_mark.mark(cur, need_to_mark_a);
m_b_mark.mark(cur, need_to_mark_b);
m_h_mark.mark(cur, need_to_mark_h);
}
}
}
/*
* ====================================
* statistics
* ====================================
*/
// debug method
void iuc_proof::dump_farkas_stats()
{
unsigned fl_total = 0;
unsigned fl_lowcut = 0;
proof_post_order it(m_pr, m);
while (it.hasNext())
{
proof* cur = it.next();
// if node is theory lemma
if (is_farkas_lemma(m, cur))
{
fl_total++;
// check whether farkas lemma is to be interpolated (could
// potentially miss farkas lemmas, which are interpolated,
// because we potentially don't want to use the lowest
// cut)
bool has_blue_nonred_parent = false;
for (unsigned i = 0; i < m.get_num_parents(cur); ++i) {
proof* premise = to_app(cur->get_arg(i));
if (!is_a_marked(premise) && is_b_marked(premise)) {
has_blue_nonred_parent = true;
break;
}
}
if (has_blue_nonred_parent && is_a_marked(cur))
{
SASSERT(is_b_marked(cur));
fl_lowcut++;
}
}
}
IF_VERBOSE(1, verbose_stream()
<< "\n total farkas lemmas " << fl_total
<< " farkas lemmas in lowest cut " << fl_lowcut << "\n";);
}
void iuc_proof::display_dot(std::ostream& out) {
out << "digraph proof { \n";
std::unordered_map<unsigned, unsigned> ids;
unsigned last_id = 0;
proof_post_order it(m_pr, m);
while (it.hasNext())
{
proof* curr = it.next();
SASSERT(ids.count(curr->get_id()) == 0);
ids.insert(std::make_pair(curr->get_id(), last_id));
std::string color = "white";
if (this->is_a_marked(curr) && !this->is_b_marked(curr))
color = "red";
else if(!this->is_a_marked(curr) && this->is_b_marked(curr))
color = "blue";
else if(this->is_a_marked(curr) && this->is_b_marked(curr) )
color = "purple";
// compute node label
std::ostringstream label_ostream;
label_ostream << mk_epp(m.get_fact(curr), m) << "\n";
std::string label = escape_dot(label_ostream.str());
// compute edge-label
std::string edge_label = "";
if (m.get_num_parents(curr) == 0) {
switch (curr->get_decl_kind())
{
case PR_ASSERTED:
edge_label = "asserted:";
break;
case PR_HYPOTHESIS:
edge_label = "hyp:";
color = "grey";
break;
case PR_TH_LEMMA:
if (is_farkas_lemma(m, curr))
edge_label = "th_axiom(farkas):";
else if (is_arith_lemma(m, curr))
edge_label = "th_axiom(arith):";
else
edge_label = "th_axiom:";
break;
default:
edge_label = "unknown axiom:";
}
}
else {
if (curr->get_decl_kind() == PR_LEMMA)
edge_label = "lemma:";
else if (curr->get_decl_kind() == PR_TH_LEMMA) {
if (is_farkas_lemma(m, curr))
edge_label = "th_lemma(farkas):";
else if (is_arith_lemma(m, curr))
edge_label = "th_lemma(arith):";
else
edge_label = "th_lemma(other):";
}
}
// generate entry for node in dot-file
out << "node_" << last_id << " " << "["
<< "shape=box,style=\"filled\","
<< "label=\"" << edge_label << " " << label << "\", "
<< "fillcolor=\"" << color << "\"" << "]\n";
// add entry for each edge to that node
for (unsigned i = m.get_num_parents(curr); i > 0 ; --i)
{
proof* premise = to_app(curr->get_arg(i-1));
unsigned pid = ids.at(premise->get_id());
out << "node_" << pid << " -> " << "node_" << last_id << ";\n";
}
++last_id;
}
out << "\n}" << std::endl;
}
}

67
src/muz/spacer/spacer_iuc_proof.h Normal file
View file

@ -0,0 +1,67 @@
#ifndef IUC_PROOF_H_
#define IUC_PROOF_H_
#include <ostream>
#include "ast/ast.h"
namespace spacer {
typedef obj_hashtable<expr> expr_set;
typedef obj_hashtable<func_decl> func_decl_set;
/*
* An iuc_proof is a proof together with information of the
* coloring of the axioms.
*/
class iuc_proof
{
public:
// Constructs an iuc_proof given an ast_manager, a proof, and a set of
// literals core_lits that might be included in the unsat core
iuc_proof(ast_manager& m, proof* pr, const expr_set& core_lits);
iuc_proof(ast_manager& m, proof* pr, const expr_ref_vector &core_lits);
// returns the proof object
proof* get() {return m_pr.get();}
// returns true if all uninterpreted symbols of e are from the core literals
// requires that m_core_symbols has already been computed
bool is_core_pure(expr* e) const;
bool is_a_marked(proof* p) {return m_a_mark.is_marked(p);}
bool is_b_marked(proof* p) {return m_b_mark.is_marked(p);}
bool is_h_marked(proof* p) {return m_h_mark.is_marked(p);}
bool is_b_pure (proof *p) {
return !is_h_marked (p) && is_core_pure(m.get_fact (p));
}
void display_dot(std::ostream &out);
// debug method
void dump_farkas_stats();
private:
ast_manager& m;
proof_ref m_pr;
ast_mark m_a_mark;
ast_mark m_b_mark;
ast_mark m_h_mark;
// -- literals that are part of the core
expr_set m_core_lits;
// symbols that occur in any literals in the core
func_decl_set m_core_symbols;
// collect symbols occurring in B (the core)
void collect_core_symbols();
// compute for each formula of the proof whether it derives
// from A or from B
void compute_marks();
};
}
#endif /* IUC_PROOF_H_ */

435
src/muz/spacer/spacer_iuc_solver.cpp Normal file
View file

@ -0,0 +1,435 @@
/**
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_iuc_solver.cpp
Abstract:
A solver that produces interpolated unsat cores (IUCs)
Author:
Arie Gurfinkel
Notes:
--*/
#include"muz/spacer/spacer_iuc_solver.h"
#include"ast/ast.h"
#include"muz/spacer/spacer_util.h"
#include"ast/proofs/proof_utils.h"
#include"muz/spacer/spacer_farkas_learner.h"
#include"ast/rewriter/expr_replacer.h"
#include"muz/spacer/spacer_unsat_core_learner.h"
#include"muz/spacer/spacer_unsat_core_plugin.h"
#include "muz/spacer/spacer_iuc_proof.h"
namespace spacer {
void iuc_solver::push ()
{
m_defs.push_back (def_manager (*this));
m_solver.push ();
}
void iuc_solver::pop (unsigned n)
{
m_solver.pop (n);
unsigned lvl = m_defs.size ();
SASSERT (n <= lvl);
unsigned new_lvl = lvl-n;
while (m_defs.size() > new_lvl) {
m_num_proxies -= m_defs.back ().m_defs.size ();
m_defs.pop_back ();
}
}
app* iuc_solver::fresh_proxy ()
{
if (m_num_proxies == m_proxies.size()) {
std::stringstream name;
name << "spacer_proxy!" << m_proxies.size ();
app_ref res(m);
res = m.mk_const (symbol (name.str ().c_str ()),
m.mk_bool_sort ());
m_proxies.push_back (res);
// -- add the new proxy to proxy eliminator
proof_ref pr(m);
pr = m.mk_asserted (m.mk_true ());
m_elim_proxies_sub.insert (res, m.mk_true (), pr);
}
return m_proxies.get (m_num_proxies++);
}
app* iuc_solver::mk_proxy (expr *v)
{
{
expr *e = v;
m.is_not (v, e);
if (is_uninterp_const(e)) { return to_app(v); }
}
def_manager &def = m_defs.size () > 0 ? m_defs.back () : m_base_defs;
return def.mk_proxy (v);
}
bool iuc_solver::mk_proxies (expr_ref_vector &v, unsigned from)
{
bool dirty = false;
for (unsigned i = from, sz = v.size(); i < sz; ++i) {
app *p = mk_proxy (v.get (i));
dirty |= (v.get (i) != p);
v[i] = p;
}
return dirty;
}
void iuc_solver::push_bg (expr *e)
{
if (m_assumptions.size () > m_first_assumption)
{ m_assumptions.shrink(m_first_assumption); }
m_assumptions.push_back (e);
m_first_assumption = m_assumptions.size ();
}
void iuc_solver::pop_bg (unsigned n)
{
if (n == 0) { return; }
if (m_assumptions.size () > m_first_assumption) {
m_assumptions.shrink(m_first_assumption);
}
m_first_assumption = m_first_assumption > n ? m_first_assumption - n : 0;
m_assumptions.shrink (m_first_assumption);
}
unsigned iuc_solver::get_num_bg () {return m_first_assumption;}
lbool iuc_solver::check_sat (unsigned num_assumptions, expr * const *assumptions)
{
// -- remove any old assumptions
m_assumptions.shrink(m_first_assumption);
// -- replace theory literals in background assumptions with proxies
mk_proxies (m_assumptions);
// -- in case mk_proxies added new literals, they are all background
m_first_assumption = m_assumptions.size ();
m_assumptions.append (num_assumptions, assumptions);
m_is_proxied = mk_proxies (m_assumptions, m_first_assumption);
return set_status (m_solver.check_sat (m_assumptions));
}
lbool iuc_solver::check_sat_cc(const expr_ref_vector &cube,
vector<expr_ref_vector> const & clauses) {
if (clauses.empty())
return check_sat(cube.size(), cube.c_ptr());
// -- remove any old assumptions
m_assumptions.shrink(m_first_assumption);
// -- replace theory literals in background assumptions with proxies
mk_proxies(m_assumptions);
// -- in case mk_proxies added new literals, they are all background
m_first_assumption = m_assumptions.size();
m_assumptions.append(cube);
m_is_proxied = mk_proxies(m_assumptions, m_first_assumption);
return set_status (m_solver.check_sat_cc(m_assumptions, clauses));
}
app* iuc_solver::def_manager::mk_proxy (expr *v)
{
app* r;
if (m_expr2proxy.find(v, r))
return r;
ast_manager &m = m_parent.m;
app* proxy = m_parent.fresh_proxy ();
app* def = m.mk_or (m.mk_not (proxy), v);
m_defs.push_back (def);
m_expr2proxy.insert (v, proxy);
m_proxy2def.insert (proxy, def);
m_parent.assert_expr (def);
return proxy;
}
bool iuc_solver::def_manager::is_proxy (app *k, app_ref &def)
{
app *r = nullptr;
bool found = m_proxy2def.find (k, r);
def = r;
return found;
}
void iuc_solver::def_manager::reset ()
{
m_expr2proxy.reset ();
m_proxy2def.reset ();
m_defs.reset ();
}
bool iuc_solver::def_manager::is_proxy_def (expr *v)
{
// XXX This might not be the most robust way to check
return m_defs.contains (v);
}
bool iuc_solver::is_proxy(expr *e, app_ref &def)
{
if (!is_uninterp_const(e))
return false;
app* a = to_app (e);
for (int i = m_defs.size (); i-- > 0; )
if (m_defs[i].is_proxy (a, def))
return true;
return m_base_defs.is_proxy (a, def);
}
void iuc_solver::collect_statistics (statistics &st) const
{
m_solver.collect_statistics (st);
st.update ("time.iuc_solver.get_iuc", m_iuc_sw.get_seconds());
st.update ("time.iuc_solver.get_iuc.hyp_reduce1", m_hyp_reduce1_sw.get_seconds());
st.update ("time.iuc_solver.get_iuc.hyp_reduce2", m_hyp_reduce2_sw.get_seconds());
st.update ("time.iuc_solver.get_iuc.learn_core", m_learn_core_sw.get_seconds());
st.update("iuc_solver.num_proxies", m_proxies.size());
}
void iuc_solver::reset_statistics ()
{
m_iuc_sw.reset();
m_hyp_reduce1_sw.reset();
m_hyp_reduce2_sw.reset();
m_learn_core_sw.reset();
}
void iuc_solver::get_unsat_core (expr_ref_vector &core) {
m_solver.get_unsat_core (core);
undo_proxies_in_core (core);
}
void iuc_solver::undo_proxies_in_core (expr_ref_vector &r)
{
app_ref e(m);
expr_fast_mark1 bg;
for (unsigned i = 0; i < m_first_assumption; ++i) {
bg.mark(m_assumptions.get(i));
}
// expand proxies
unsigned j = 0;
for (expr* rr : r) {
// skip background assumptions
if (bg.is_marked(rr))
continue;
// -- undo proxies, but only if they were introduced in check_sat
if (m_is_proxied && is_proxy(rr, e)) {
SASSERT (m.is_or (e));
r[j++] = e->get_arg (1);
}
else {
r[j++] = rr;
}
}
r.shrink (j);
}
void iuc_solver::undo_proxies (expr_ref_vector &r)
{
app_ref e(m);
// expand proxies
for (unsigned i = 0, sz = r.size (); i < sz; ++i)
if (is_proxy(r.get(i), e)) {
SASSERT (m.is_or (e));
r[i] = e->get_arg (1);
}
}
void iuc_solver::elim_proxies (expr_ref_vector &v)
{
expr_ref f = mk_and (v);
scoped_ptr<expr_replacer> rep = mk_expr_simp_replacer (m);
rep->set_substitution (&m_elim_proxies_sub);
(*rep)(f);
v.reset();
flatten_and(f, v);
}
void iuc_solver::get_iuc(expr_ref_vector &core)
{
scoped_watch _t_ (m_iuc_sw);
typedef obj_hashtable<expr> expr_set;
expr_set core_lits;
for (unsigned i = m_first_assumption, sz = m_assumptions.size(); i < sz; ++i) {
expr *a = m_assumptions.get (i);
app_ref def(m);
if (is_proxy(a, def)) { core_lits.insert(def.get()); }
core_lits.insert (a);
}
if (m_iuc == 0) {
// ORIGINAL PDR CODE
// AG: deprecated
proof_ref pr(m);
pr = get_proof ();
farkas_learner learner_old;
learner_old.set_split_literals(m_split_literals);
learner_old.get_lemmas (pr, core_lits, core);
elim_proxies (core);
simplify_bounds (core); // XXX potentially redundant
}
else {
// NEW IUC
proof_ref res(get_proof(), m);
// -- old hypothesis reducer while the new one is broken
if (m_old_hyp_reducer) {
scoped_watch _t_ (m_hyp_reduce1_sw);
// AG: deprecated
// pre-process proof in order to get a proof which is
// better suited for unsat-core-extraction
if (m_print_farkas_stats) {
iuc_proof iuc_before(m, res.get(), core_lits);
verbose_stream() << "\nOld reduce_hypotheses. Before:";
iuc_before.dump_farkas_stats();
}
proof_utils::reduce_hypotheses(res);
proof_utils::permute_unit_resolution(res);
if (m_print_farkas_stats) {
iuc_proof iuc_after(m, res.get(), core_lits);
verbose_stream() << "Old reduce_hypothesis. After:";
iuc_after.dump_farkas_stats();
}
}
// -- new hypothesis reducer
else
{
scoped_watch _t_ (m_hyp_reduce2_sw);
// pre-process proof for better iuc extraction
if (m_print_farkas_stats) {
iuc_proof iuc_before(m, res.get(), core_lits);
verbose_stream() << "\n New hypothesis_reducer. Before:";
iuc_before.dump_farkas_stats();
}
proof_ref pr1(m);
{
scoped_watch _t_ (m_hyp_reduce1_sw);
theory_axiom_reducer ta_reducer(m);
pr1 = ta_reducer.reduce (res.get());
}
proof_ref pr2(m);
{
scoped_watch _t_ (m_hyp_reduce2_sw);
hypothesis_reducer hyp_reducer(m);
pr2 = hyp_reducer.reduce(pr1);
}
res = pr2;
if (m_print_farkas_stats) {
iuc_proof iuc_after(m, res.get(), core_lits);
verbose_stream() << "New hypothesis_reducer. After:";
iuc_after.dump_farkas_stats();
}
}
iuc_proof iuc_pf(m, res, core_lits);
unsat_core_learner learner(m, iuc_pf);
unsat_core_plugin* plugin;
// -- register iuc plugins
switch (m_iuc_arith) {
case 0:
case 1:
plugin =
alloc(unsat_core_plugin_farkas_lemma,
learner, m_split_literals,
(m_iuc_arith == 1) /* use constants from A */);
learner.register_plugin(plugin);
break;
case 2:
SASSERT(false && "Broken");
plugin = alloc(unsat_core_plugin_farkas_lemma_optimized, learner, m);
learner.register_plugin(plugin);
break;
case 3:
plugin = alloc(unsat_core_plugin_farkas_lemma_bounded, learner, m);
learner.register_plugin(plugin);
break;
default:
UNREACHABLE();
break;
}
switch (m_iuc) {
case 1:
// -- iuc based on the lowest cut in the proof
plugin = alloc(unsat_core_plugin_lemma, learner);
learner.register_plugin(plugin);
break;
case 2:
// -- iuc based on the smallest cut in the proof
plugin = alloc(unsat_core_plugin_min_cut, learner, m);
learner.register_plugin(plugin);
break;
default:
UNREACHABLE();
break;
}
{
scoped_watch _t_ (m_learn_core_sw);
// compute interpolating unsat core
learner.compute_unsat_core(core);
}
elim_proxies (core);
// AG: this should be taken care of by minimizing the iuc cut
simplify_bounds (core);
}
IF_VERBOSE(2,
verbose_stream () << "IUC Core:\n" << core << "\n";);
}
void iuc_solver::refresh ()
{
// only refresh in non-pushed state
SASSERT (m_defs.empty());
expr_ref_vector assertions (m);
for (unsigned i = 0, e = m_solver.get_num_assertions(); i < e; ++i) {
expr* a = m_solver.get_assertion (i);
if (!m_base_defs.is_proxy_def(a)) { assertions.push_back(a); }
}
m_base_defs.reset ();
NOT_IMPLEMENTED_YET ();
// solver interface does not have a reset method. need to introduce it somewhere.
// m_solver.reset ();
for (unsigned i = 0, e = assertions.size (); i < e; ++i)
{ m_solver.assert_expr(assertions.get(i)); }
}
}

181
src/muz/spacer/spacer_iuc_solver.h Normal file
View file

@ -0,0 +1,181 @@
/**
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_iuc_solver.h
Abstract:
A solver that produces interpolated unsat cores
Author:
Arie Gurfinkel
Notes:
--*/
#ifndef SPACER_IUC_SOLVER_H_
#define SPACER_IUC_SOLVER_H_
#include"solver/solver.h"
#include"ast/expr_substitution.h"
#include"util/stopwatch.h"
namespace spacer {
class iuc_solver : public solver {
private:
struct def_manager {
iuc_solver & m_parent;
expr_ref_vector m_defs;
obj_map<expr, app*> m_expr2proxy;
obj_map<app, app*> m_proxy2def;
def_manager(iuc_solver &parent) :
m_parent(parent), m_defs(m_parent.m)
{}
bool is_proxy(app *k, app_ref &v);
app* mk_proxy(expr *v);
void reset();
bool is_proxy_def(expr *v);
};
friend struct def_manager;
ast_manager& m;
solver& m_solver;
app_ref_vector m_proxies;
unsigned m_num_proxies;
vector<def_manager> m_defs;
def_manager m_base_defs;
expr_ref_vector m_assumptions;
unsigned m_first_assumption;
bool m_is_proxied;
stopwatch m_iuc_sw;
stopwatch m_hyp_reduce1_sw;
stopwatch m_hyp_reduce2_sw;
stopwatch m_learn_core_sw;
expr_substitution m_elim_proxies_sub;
bool m_split_literals;
unsigned m_iuc;
unsigned m_iuc_arith;
bool m_print_farkas_stats;
bool m_old_hyp_reducer;
bool is_proxy(expr *e, app_ref &def);
void undo_proxies_in_core(expr_ref_vector &v);
app* mk_proxy(expr *v);
app* fresh_proxy();
void elim_proxies(expr_ref_vector &v);
public:
iuc_solver(solver &solver, unsigned iuc, unsigned iuc_arith,
bool print_farkas_stats, bool old_hyp_reducer,
bool split_literals = false) :
m(solver.get_manager()),
m_solver(solver),
m_proxies(m),
m_num_proxies(0),
m_base_defs(*this),
m_assumptions(m),
m_first_assumption(0),
m_is_proxied(false),
m_elim_proxies_sub(m, false, true),
m_split_literals(split_literals),
m_iuc(iuc),
m_iuc_arith(iuc_arith),
m_print_farkas_stats(print_farkas_stats),
m_old_hyp_reducer(old_hyp_reducer)
{}
~iuc_solver() override {}
/* iuc solver specific */
virtual void get_iuc(expr_ref_vector &core);
void set_split_literals(bool v) { m_split_literals = v; }
bool mk_proxies(expr_ref_vector &v, unsigned from = 0);
void undo_proxies(expr_ref_vector &v);
void push_bg(expr *e);
void pop_bg(unsigned n);
unsigned get_num_bg();
void get_full_unsat_core(ptr_vector<expr> &core) {
expr_ref_vector _core(m);
m_solver.get_unsat_core(_core);
core.append(_core.size(), _core.c_ptr());
}
/* solver interface */
solver* translate(ast_manager &m, params_ref const &p) override {
return m_solver.translate(m, p);
}
void updt_params(params_ref const &p) override { m_solver.updt_params(p); }
void reset_params(params_ref const &p) override { m_solver.reset_params(p); }
const params_ref &get_params() const override { return m_solver.get_params(); }
void push_params() override { m_solver.push_params(); }
void pop_params() override { m_solver.pop_params(); }
void collect_param_descrs(param_descrs &r) override { m_solver.collect_param_descrs(r); }
void set_produce_models(bool f) override { m_solver.set_produce_models(f); }
void assert_expr_core(expr *t) override { m_solver.assert_expr(t); }
void assert_expr_core2(expr *t, expr *a) override { NOT_IMPLEMENTED_YET(); }
expr_ref_vector cube(expr_ref_vector&, unsigned) override { return expr_ref_vector(m); }
void push() override;
void pop(unsigned n) override;
unsigned get_scope_level() const override { return m_solver.get_scope_level(); }
lbool check_sat(unsigned num_assumptions, expr * const *assumptions) override;
lbool check_sat_cc(const expr_ref_vector &cube, vector<expr_ref_vector> const & clauses) override;
void set_progress_callback(progress_callback *callback) override {
m_solver.set_progress_callback(callback);
}
unsigned get_num_assertions() const override { return m_solver.get_num_assertions(); }
expr * get_assertion(unsigned idx) const override { return m_solver.get_assertion(idx); }
unsigned get_num_assumptions() const override { return m_solver.get_num_assumptions(); }
expr * get_assumption(unsigned idx) const override { return m_solver.get_assumption(idx); }
std::ostream &display(std::ostream &out, unsigned n, expr* const* es) const override {
return m_solver.display(out, n, es);
}
/* check_sat_result interface */
void collect_statistics(statistics &st) const override ;
virtual void reset_statistics();
void get_unsat_core(expr_ref_vector &r) override;
void get_model_core(model_ref &m) override {m_solver.get_model(m);}
proof *get_proof() override {return m_solver.get_proof();}
std::string reason_unknown() const override { return m_solver.reason_unknown(); }
void set_reason_unknown(char const* msg) override { m_solver.set_reason_unknown(msg); }
void get_labels(svector<symbol> &r) override { m_solver.get_labels(r); }
ast_manager& get_manager() const override { return m; }
virtual void refresh();
class scoped_mk_proxy {
iuc_solver &m_s;
expr_ref_vector &m_v;
public:
scoped_mk_proxy(iuc_solver &s, expr_ref_vector &v) : m_s(s), m_v(v) {
m_s.mk_proxies(m_v);
}
~scoped_mk_proxy() { m_s.undo_proxies(m_v); }
};
class scoped_bg {
iuc_solver &m_s;
unsigned m_bg_sz;
public:
scoped_bg(iuc_solver &s) : m_s(s), m_bg_sz(m_s.get_num_bg()) {}
~scoped_bg() {
if (m_s.get_num_bg() > m_bg_sz) {
m_s.pop_bg(m_s.get_num_bg() - m_bg_sz);
}
}
};
};
}
#endif

191
src/muz/spacer/spacer_json.cpp Normal file
View file

@ -0,0 +1,191 @@
/**++
Copyright (c) 2017 Microsoft Corporation and Matteo Marescotti
Module Name:
spacer_json.cpp
Abstract:
SPACER json marshalling support
Author:
Matteo Marescotti
Notes:
--*/
#include <iomanip>
#include "spacer_context.h"
#include "spacer_json.h"
#include "spacer_util.h"
namespace spacer {
static std::ostream &json_marshal(std::ostream &out, ast *t, ast_manager &m) {
mk_epp pp = mk_epp(t, m);
std::ostringstream ss;
ss << pp;
out << "\"";
for (auto &c:ss.str()) {
switch (c) {
case '"':
out << "\\\"";
break;
case '\\':
out << "\\\\";
break;
case '\b':
out << "\\b";
break;
case '\f':
out << "\\f";
break;
case '\n':
out << "\\n";
break;
case '\r':
out << "\\r";
break;
case '\t':
out << "\\t";
break;
default:
if ('\x00' <= c && c <= '\x1f') {
out << "\\u"
<< std::hex << std::setw(4) << std::setfill('0') << (int) c;
} else {
out << c;
}
}
}
out << "\"";
return out;
}
static std::ostream &json_marshal(std::ostream &out, lemma *l) {
out << "{"
<< R"("init_level":")" << l->init_level()
<< R"(", "level":")" << l->level()
<< R"(", "expr":)";
json_marshal(out, l->get_expr(), l->get_ast_manager());
out << "}";
return out;
}
static std::ostream &json_marshal(std::ostream &out, const lemma_ref_vector &lemmas) {
std::ostringstream ls;
for (auto l:lemmas) {
ls << ((unsigned)ls.tellp() == 0 ? "" : ",");
json_marshal(ls, l);
}
out << "[" << ls.str() << "]";
return out;
}
void json_marshaller::register_lemma(lemma *l) {
if (l->has_pob()) {
m_relations[&*l->get_pob()][l->get_pob()->depth()].push_back(l);
}
}
void json_marshaller::register_pob(pob *p) {
m_relations[p];
}
void json_marshaller::marshal_lemmas_old(std::ostream &out) const {
unsigned pob_id = 0;
for (auto &pob_map:m_relations) {
std::ostringstream pob_lemmas;
for (auto &depth_lemmas : pob_map.second) {
pob_lemmas << ((unsigned)pob_lemmas.tellp() == 0 ? "" : ",")
<< "\"" << depth_lemmas.first << "\":";
json_marshal(pob_lemmas, depth_lemmas.second);
}
if (pob_lemmas.tellp()) {
out << ((unsigned)out.tellp() == 0 ? "" : ",\n");
out << "\"" << pob_id << "\":{" << pob_lemmas.str() << "}";
}
pob_id++;
}
}
void json_marshaller::marshal_lemmas_new(std::ostream &out) const {
unsigned pob_id = 0;
for (auto &pob_map:m_relations) {
std::ostringstream pob_lemmas;
pob *n = pob_map.first;
unsigned i = 0;
for (auto *l : n->lemmas()) {
pob_lemmas << ((unsigned)pob_lemmas.tellp() == 0 ? "" : ",")
<< "\"" << i++ << "\":";
lemma_ref_vector lemmas_vec;
lemmas_vec.push_back(l);
json_marshal(pob_lemmas, lemmas_vec);
}
if (pob_lemmas.tellp()) {
out << ((unsigned)out.tellp() == 0 ? "" : ",\n");
out << "\"" << pob_id << "\":{" << pob_lemmas.str() << "}";
}
pob_id++;
}
}
std::ostream &json_marshaller::marshal(std::ostream &out) const {
std::ostringstream nodes;
std::ostringstream edges;
std::ostringstream lemmas;
if (m_old_style)
marshal_lemmas_old(lemmas);
else
marshal_lemmas_new(lemmas);
unsigned pob_id = 0;
unsigned depth = 0;
while (true) {
double root_expand_time = m_ctx->get_root().get_expand_time(depth);
bool a = false;
pob_id = 0;
for (auto &pob_map:m_relations) {
pob *n = pob_map.first;
double expand_time = n->get_expand_time(depth);
if (expand_time > 0) {
a = true;
std::ostringstream pob_expr;
json_marshal(pob_expr, n->post(), n->get_ast_manager());
nodes << ((unsigned)nodes.tellp() == 0 ? "" : ",\n") <<
"{\"id\":\"" << depth << n <<
"\",\"relative_time\":\"" << expand_time / root_expand_time <<
"\",\"absolute_time\":\"" << std::setprecision(2) << expand_time <<
"\",\"predicate\":\"" << n->pt().head()->get_name() <<
"\",\"expr_id\":\"" << n->post()->get_id() <<
"\",\"pob_id\":\"" << pob_id <<
"\",\"depth\":\"" << depth <<
"\",\"expr\":" << pob_expr.str() << "}";
if (n->parent()) {
edges << ((unsigned)edges.tellp() == 0 ? "" : ",\n") <<
"{\"from\":\"" << depth << n->parent() <<
"\",\"to\":\"" << depth << n << "\"}";
}
}
pob_id++;
}
if (!a) {
break;
}
depth++;
}
out << "{\n\"nodes\":[\n" << nodes.str() << "\n],\n";
out << "\"edges\":[\n" << edges.str() << "\n],\n";
out << "\"lemmas\":{\n" << lemmas.str() << "\n}\n}\n";
return out;
}
}

61
src/muz/spacer/spacer_json.h Normal file
View file

@ -0,0 +1,61 @@
/**++
Copyright (c) 2017 Microsoft Corporation and Matteo Marescotti
Module Name:
spacer_json.h
Abstract:
SPACER json marshalling support
Author:
Matteo Marescotti
Notes:
--*/
#ifndef Z3_SPACER_JSON_H
#define Z3_SPACER_JSON_H
#include<iostream>
#include<map>
#include "util/ref.h"
#include "util/ref_vector.h"
class ast;
class ast_manager;
namespace spacer {
class lemma;
typedef sref_vector<lemma> lemma_ref_vector;
class context;
class pob;
class json_marshaller {
context *m_ctx;
bool m_old_style;
std::map<pob*, std::map<unsigned, lemma_ref_vector>> m_relations;
void marshal_lemmas_old(std::ostream &out) const;
void marshal_lemmas_new(std::ostream &out) const;
public:
json_marshaller(context *ctx, bool old_style = false) :
m_ctx(ctx), m_old_style(old_style) {}
void register_lemma(lemma *l);
void register_pob(pob *p);
std::ostream &marshal(std::ostream &out) const;
};
}
#endif //Z3_SPACER_JSON_H

2
src/muz/spacer/spacer_legacy_mbp.cpp
View file

@ -99,7 +99,7 @@ void qe_project(ast_manager& m, app_ref_vector& vars, expr_ref& fml, model_ref&
);
{
scoped_no_proof _sp(m);
qe::arith_project(*M, arith_vars, fml, map);
spacer_qe::arith_project(*M, arith_vars, fml, map);
}
SASSERT(arith_vars.empty());
TRACE("spacer",

5
src/muz/spacer/spacer_legacy_mev.cpp
View file

@ -138,7 +138,6 @@ void model_evaluator::process_formula(app* e, ptr_vector<expr>& todo, ptr_vector
case OP_FALSE:
break;
case OP_EQ:
case OP_IFF:
if (args[0] == args[1]) {
SASSERT(v);
// no-op
@ -634,10 +633,6 @@ void model_evaluator::eval_basic(app* e)
set_x(e);
}
break;
case OP_IFF:
VERIFY(m.is_iff(e, arg1, arg2));
eval_eq(e, arg1, arg2);
break;
case OP_XOR:
VERIFY(m.is_xor(e, arg1, arg2));
eval_eq(e, arg1, arg2);

207
src/muz/spacer/spacer_manager.cpp
View file

@ -30,6 +30,7 @@ Revision History:
#include "model/model_smt2_pp.h"
#include "tactic/model_converter.h"
#include "smt/smt_solver.h"
namespace spacer {
class collect_decls_proc {
@ -168,167 +169,30 @@ void inductive_property::display(datalog::rule_manager& rm, ptr_vector<datalog::
}
}
std::vector<std::string> manager::get_state_suffixes()
{
std::vector<std::string> res;
res.push_back("_n");
return res;
}
manager::manager(unsigned max_num_contexts, ast_manager& manager) :
m(manager),
m_brwr(m),
m_mux(m, get_state_suffixes()),
m_background(m.mk_true(), m),
m_contexts(m, max_num_contexts),
m_contexts2(m, max_num_contexts),
m_contexts3(m, max_num_contexts),
m_next_unique_num(0)
{
}
void manager::add_new_state(func_decl * s)
{
SASSERT(s->get_arity() == 0); //we currently don't support non-constant states
decl_vector vect;
manager::manager(ast_manager& manager) : m(manager), m_mux(m) {}
SASSERT(o_index(0) == 1); //we assume this in the number of retrieved symbols
m_mux.create_tuple(s, s->get_arity(), s->get_domain(), s->get_range(), 2, vect);
m_o0_preds.push_back(vect[o_index(0)]);
}
func_decl * manager::get_o_pred(func_decl* s, unsigned idx)
{
func_decl * res = m_mux.try_get_by_prefix(s, o_index(idx));
if (res) { return res; }
add_new_state(s);
res = m_mux.try_get_by_prefix(s, o_index(idx));
func_decl * manager::get_o_pred(func_decl* s, unsigned idx) {
func_decl * res = m_mux.find_by_decl(s, o_index(idx));
if (!res) {
m_mux.register_decl(s);
res = m_mux.find_by_decl(s, o_index(idx));
}
SASSERT(res);
return res;
}
func_decl * manager::get_n_pred(func_decl* s)
{
func_decl * res = m_mux.try_get_by_prefix(s, n_index());
if (res) { return res; }
add_new_state(s);
res = m_mux.try_get_by_prefix(s, n_index());
func_decl * manager::get_n_pred(func_decl* s) {
func_decl * res = m_mux.find_by_decl(s, n_index());
if (!res) {
m_mux.register_decl(s);
res = m_mux.find_by_decl(s, n_index());
}
SASSERT(res);
return res;
}
void manager::mk_model_into_cube(const expr_ref_vector & mdl, expr_ref & res)
{
m_brwr.mk_and(mdl.size(), mdl.c_ptr(), res);
}
void manager::mk_core_into_cube(const expr_ref_vector & core, expr_ref & res)
{
m_brwr.mk_and(core.size(), core.c_ptr(), res);
}
void manager::mk_cube_into_lemma(expr * cube, expr_ref & res)
{
m_brwr.mk_not(cube, res);
}
void manager::mk_lemma_into_cube(expr * lemma, expr_ref & res)
{
m_brwr.mk_not(lemma, res);
}
expr_ref manager::mk_and(unsigned sz, expr* const* exprs)
{
expr_ref result(m);
m_brwr.mk_and(sz, exprs, result);
return result;
}
expr_ref manager::mk_or(unsigned sz, expr* const* exprs)
{
expr_ref result(m);
m_brwr.mk_or(sz, exprs, result);
return result;
}
expr_ref manager::mk_not_and(expr_ref_vector const& conjs)
{
expr_ref result(m), e(m);
expr_ref_vector es(conjs);
flatten_and(es);
for (unsigned i = 0; i < es.size(); ++i) {
m_brwr.mk_not(es[i].get(), e);
es[i] = e;
}
m_brwr.mk_or(es.size(), es.c_ptr(), result);
return result;
}
void manager::get_or(expr* e, expr_ref_vector& result)
{
result.push_back(e);
for (unsigned i = 0; i < result.size();) {
e = result[i].get();
if (m.is_or(e)) {
result.append(to_app(e)->get_num_args(), to_app(e)->get_args());
result[i] = result.back();
result.pop_back();
} else {
++i;
}
}
}
bool manager::try_get_state_and_value_from_atom(expr * atom0, app *& state, app_ref& value)
{
if (!is_app(atom0)) {
return false;
}
app * atom = to_app(atom0);
expr * arg1;
expr * arg2;
app * candidate_state;
app_ref candidate_value(m);
if (m.is_not(atom, arg1)) {
if (!is_app(arg1)) {
return false;
}
candidate_state = to_app(arg1);
candidate_value = m.mk_false();
} else if (m.is_eq(atom, arg1, arg2)) {
if (!is_app(arg1) || !is_app(arg2)) {
return false;
}
if (!m_mux.is_muxed(to_app(arg1)->get_decl())) {
std::swap(arg1, arg2);
}
candidate_state = to_app(arg1);
candidate_value = to_app(arg2);
} else {
candidate_state = atom;
candidate_value = m.mk_true();
}
if (!m_mux.is_muxed(candidate_state->get_decl())) {
return false;
}
state = candidate_state;
value = candidate_value;
return true;
}
bool manager::try_get_state_decl_from_atom(expr * atom, func_decl *& state)
{
app_ref dummy_value_holder(m);
app * s;
if (try_get_state_and_value_from_atom(atom, s, dummy_value_holder)) {
state = s->get_decl();
return true;
} else {
return false;
}
}
/**
* Create a new skolem constant
*/
@ -340,22 +204,27 @@ app* mk_zk_const(ast_manager &m, unsigned idx, sort *s) {
namespace find_zk_const_ns {
struct proc {
int m_max;
app_ref_vector &m_out;
proc (app_ref_vector &out) : m_out(out) {}
proc (app_ref_vector &out) : m_max(-1), m_out(out) {}
void operator() (var const * n) const {}
void operator() (app *n) const {
if (is_uninterp_const(n) &&
n->get_decl()->get_name().str().compare (0, 3, "sk!") == 0) {
m_out.push_back (n);
void operator() (app *n) {
int idx;
if (is_zk_const(n, idx)) {
m_out.push_back(n);
if (idx > m_max) {
m_max = idx;
}
}
}
void operator() (quantifier const *n) const {}
};
}
void find_zk_const(expr *e, app_ref_vector &res) {
int find_zk_const(expr *e, app_ref_vector &res) {
find_zk_const_ns::proc p(res);
for_each_expr (p, e);
return p.m_max;
}
namespace has_zk_const_ns {
@ -363,8 +232,8 @@ struct found {};
struct proc {
void operator() (var const *n) const {}
void operator() (app const *n) const {
if (is_uninterp_const(n) &&
n->get_decl()->get_name().str().compare(0, 3, "sk!") == 0) {
int idx;
if (is_zk_const(n, idx)) {
throw found();
}
}
@ -384,4 +253,26 @@ bool has_zk_const(expr *e){
return false;
}
bool is_zk_const (const app *a, int &n) {
if (!is_uninterp_const(a)) return false;
const symbol &name = a->get_decl()->get_name();
if (name.str().compare (0, 3, "sk!") != 0) {
return false;
}
n = std::stoi(name.str().substr(3));
return true;
}
bool sk_lt_proc::operator()(const app *a1, const app *a2) {
if (a1 == a2) return false;
int n1, n2;
bool z1, z2;
z1 = is_zk_const(a1, n1);
z2 = is_zk_const(a2, n2);
if (z1 && z2) return n1 < n2;
if (z1 != z2) return z1;
return ast_lt_proc()(a1, a2);
}
}

277
src/muz/spacer/spacer_manager.h
View file

@ -13,6 +13,7 @@ Abstract:
Author:
Krystof Hoder (t-khoder) 2011-8-25.
Arie Gurfinkel
Revision History:
@ -34,12 +35,10 @@ Revision History:
#include "muz/spacer/spacer_util.h"
#include "muz/spacer/spacer_sym_mux.h"
#include "muz/spacer/spacer_farkas_learner.h"
#include "muz/spacer/spacer_smt_context_manager.h"
#include "muz/base/dl_rule.h"
namespace smt {
class context;
}
#include "solver/solver.h"
#include "solver/solver_pool.h"
namespace smt {class context;}
namespace spacer {
@ -67,280 +66,74 @@ public:
m_relation_info(relations) {}
std::string to_string() const;
expr_ref to_expr() const;
void to_model(model_ref& md) const;
void display(datalog::rule_manager& rm, ptr_vector<datalog::rule> const& rules, std::ostream& out) const;
void display(datalog::rule_manager& rm,
ptr_vector<datalog::rule> const& rules,
std::ostream& out) const;
};
class manager {
ast_manager& m;
mutable bool_rewriter m_brwr;
// manager of multiplexed names
sym_mux m_mux;
expr_ref m_background;
decl_vector m_o0_preds;
spacer::smt_context_manager m_contexts;
spacer::smt_context_manager m_contexts2;
spacer::smt_context_manager m_contexts3;
/** whenever we need an unique number, we get this one and increase */
unsigned m_next_unique_num;
static std::vector<std::string> get_state_suffixes();
unsigned n_index() const { return 0; }
unsigned o_index(unsigned i) const { return i + 1; }
void add_new_state(func_decl * s);
public:
manager(unsigned max_num_contexts, ast_manager & manager);
manager(ast_manager & manager);
ast_manager& get_manager() const { return m; }
bool_rewriter& get_brwr() const { return m_brwr; }
expr_ref mk_and(unsigned sz, expr* const* exprs);
expr_ref mk_and(expr_ref_vector const& exprs)
{
return mk_and(exprs.size(), exprs.c_ptr());
}
expr_ref mk_and(expr* a, expr* b)
{
expr* args[2] = { a, b };
return mk_and(2, args);
}
expr_ref mk_or(unsigned sz, expr* const* exprs);
expr_ref mk_or(expr_ref_vector const& exprs)
{
return mk_or(exprs.size(), exprs.c_ptr());
}
expr_ref mk_not_and(expr_ref_vector const& exprs);
void get_or(expr* e, expr_ref_vector& result);
// management of mux names
//"o" predicates stand for the old states and "n" for the new states
func_decl * get_o_pred(func_decl * s, unsigned idx);
func_decl * get_n_pred(func_decl * s);
/**
Marks symbol as non-model which means it will not appear in models collected by
get_state_cube_from_model function.
This is to take care of auxiliary symbols introduced by the disjunction relations
to relativize lemmas coming from disjuncts.
*/
void mark_as_non_model(func_decl * p)
{
m_mux.mark_as_non_model(p);
}
func_decl * const * begin_o0_preds() const { return m_o0_preds.begin(); }
func_decl * const * end_o0_preds() const { return m_o0_preds.end(); }
bool is_state_pred(func_decl * p) const { return m_mux.is_muxed(p); }
func_decl * to_o0(func_decl * p) { return m_mux.conv(m_mux.get_primary(p), 0, o_index(0)); }
bool is_o(func_decl * p, unsigned idx) const
{
return m_mux.has_index(p, o_index(idx));
}
void get_o_index(func_decl* p, unsigned& idx) const
{
m_mux.try_get_index(p, idx);
SASSERT(idx != n_index());
idx--; // m_mux has indices starting at 1
}
bool is_o(expr* e, unsigned idx) const
{
return is_app(e) && is_o(to_app(e)->get_decl(), idx);
}
bool is_o(func_decl * p) const
{
unsigned idx;
return m_mux.try_get_index(p, idx) && idx != n_index();
}
bool is_o(expr* e) const
{
return is_app(e) && is_o(to_app(e)->get_decl());
}
bool is_n(func_decl * p) const
{
return m_mux.has_index(p, n_index());
}
bool is_n(expr* e) const
{
return is_app(e) && is_n(to_app(e)->get_decl());
}
/** true if p should not appead in models propagates into child relations */
bool is_non_model_sym(func_decl * p) const
{ return m_mux.is_non_model_sym(p); }
/** true if f doesn't contain any n predicates */
bool is_o_formula(expr * f) const
{
return !m_mux.contains(f, n_index());
}
/** true if f contains only o state preds of index o_idx */
bool is_o_formula(expr * f, unsigned o_idx) const
{
return m_mux.is_homogenous_formula(f, o_index(o_idx));
}
/** true if f doesn't contain any o predicates */
bool is_n_formula(expr * f) const
{
return m_mux.is_homogenous_formula(f, n_index());
}
{return m_mux.is_homogenous_formula(f, n_index());}
func_decl * o2n(func_decl * p, unsigned o_idx) const
{
return m_mux.conv(p, o_index(o_idx), n_index());
}
{return m_mux.shift_decl(p, o_index(o_idx), n_index());}
func_decl * o2o(func_decl * p, unsigned src_idx, unsigned tgt_idx) const
{
return m_mux.conv(p, o_index(src_idx), o_index(tgt_idx));
}
{return m_mux.shift_decl(p, o_index(src_idx), o_index(tgt_idx));}
func_decl * n2o(func_decl * p, unsigned o_idx) const
{
return m_mux.conv(p, n_index(), o_index(o_idx));
}
{return m_mux.shift_decl(p, n_index(), o_index(o_idx));}
void formula_o2n(expr * f, expr_ref & result, unsigned o_idx, bool homogenous = true) const
{ m_mux.conv_formula(f, o_index(o_idx), n_index(), result, homogenous); }
void formula_o2n(expr * f, expr_ref & result, unsigned o_idx,
bool homogenous = true) const
{m_mux.shift_expr(f, o_index(o_idx), n_index(), result, homogenous);}
void formula_n2o(expr * f, expr_ref & result, unsigned o_idx, bool homogenous = true) const
{ m_mux.conv_formula(f, n_index(), o_index(o_idx), result, homogenous); }
void formula_n2o(expr * f, expr_ref & result, unsigned o_idx,
bool homogenous = true) const
{m_mux.shift_expr(f, n_index(), o_index(o_idx), result, homogenous);}
void formula_n2o(unsigned o_idx, bool homogenous, expr_ref & result) const
{ m_mux.conv_formula(result.get(), n_index(), o_index(o_idx), result, homogenous); }
{m_mux.shift_expr(result.get(), n_index(), o_index(o_idx),
result, homogenous);}
void formula_o2o(expr * src, expr_ref & tgt, unsigned src_idx, unsigned tgt_idx, bool homogenous = true) const
{ m_mux.conv_formula(src, o_index(src_idx), o_index(tgt_idx), tgt, homogenous); }
void formula_o2o(expr * src, expr_ref & tgt, unsigned src_idx,
unsigned tgt_idx, bool homogenous = true) const
{m_mux.shift_expr(src, o_index(src_idx), o_index(tgt_idx),
tgt, homogenous);}
/**
Return true if all state symbols which e contains are of one kind (either "n" or one of "o").
*/
bool is_homogenous_formula(expr * e) const
{
return m_mux.is_homogenous_formula(e);
}
/**
Collect indices used in expression.
*/
void collect_indices(expr* e, unsigned_vector& indices) const
{
m_mux.collect_indices(e, indices);
}
/**
Collect used variables of each index.
*/
void collect_variables(expr* e, vector<ptr_vector<app> >& vars) const
{
m_mux.collect_variables(e, vars);
}
/**
Return true iff both s1 and s2 are either "n" or "o" of the same index.
If one (or both) of them are not state symbol, return false.
*/
bool have_different_state_kinds(func_decl * s1, func_decl * s2) const
{
unsigned i1, i2;
return m_mux.try_get_index(s1, i1) && m_mux.try_get_index(s2, i2) && i1 != i2;
}
/**
Increase indexes of state symbols in formula by dist.
The 'N' index becomes 'O' index with number dist-1.
*/
void formula_shift(expr * src, expr_ref & tgt, unsigned dist) const
{
SASSERT(n_index() == 0);
SASSERT(o_index(0) == 1);
m_mux.shift_formula(src, dist, tgt);
}
void mk_model_into_cube(const expr_ref_vector & mdl, expr_ref & res);
void mk_core_into_cube(const expr_ref_vector & core, expr_ref & res);
void mk_cube_into_lemma(expr * cube, expr_ref & res);
void mk_lemma_into_cube(expr * lemma, expr_ref & res);
/**
Remove from vec all atoms that do not have an "o" state.
The order of elements in vec may change.
An assumption is that atoms having "o" state of given index
do not have "o" states of other indexes or "n" states.
*/
void filter_o_atoms(expr_ref_vector& vec, unsigned o_idx) const
{ m_mux.filter_idx(vec, o_index(o_idx)); }
void filter_n_atoms(expr_ref_vector& vec) const
{ m_mux.filter_idx(vec, n_index()); }
/**
Partition literals into o_lits and others.
*/
void partition_o_atoms(expr_ref_vector const& lits,
expr_ref_vector& o_lits,
expr_ref_vector& other,
unsigned o_idx) const
{
m_mux.partition_o_idx(lits, o_lits, other, o_index(o_idx));
}
void filter_out_non_model_atoms(expr_ref_vector& vec) const
{ m_mux.filter_non_model_lits(vec); }
bool try_get_state_and_value_from_atom(expr * atom, app *& state, app_ref& value);
bool try_get_state_decl_from_atom(expr * atom, func_decl *& state);
std::string pp_model(const model_core & mdl) const
{ return m_mux.pp_model(mdl); }
void set_background(expr* b) { m_background = b; }
expr* get_background() const { return m_background; }
unsigned get_unique_num() { return m_next_unique_num++; }
solver* mk_fresh() {return m_contexts.mk_fresh();}
smt_params& fparams() { return m_contexts.fparams(); }
solver* mk_fresh2() {return m_contexts2.mk_fresh();}
smt_params &fparams2() { return m_contexts2.fparams(); }
solver* mk_fresh3() {return m_contexts3.mk_fresh();}
smt_params &fparams3() {return m_contexts3.fparams();}
void collect_statistics(statistics& st) const
{
m_contexts.collect_statistics(st);
m_contexts2.collect_statistics(st);
m_contexts3.collect_statistics(st);
}
void reset_statistics()
{
m_contexts.reset_statistics();
m_contexts2.reset_statistics();
m_contexts3.reset_statistics();
}
};
/** Skolem constants for quantified spacer */
app* mk_zk_const (ast_manager &m, unsigned idx, sort *s);
void find_zk_const(expr* e, app_ref_vector &out);
int find_zk_const(expr* e, app_ref_vector &out);
inline int find_zk_const(expr_ref_vector const &v, app_ref_vector &out)
{return find_zk_const (mk_and(v), out);}
bool has_zk_const(expr* e);
bool is_zk_const (const app *a, int &n);
struct sk_lt_proc {bool operator()(const app* a1, const app* a2);};
}
#endif

102
src/muz/spacer/spacer_mbc.cpp Normal file
View file

@ -0,0 +1,102 @@
#include <climits>
#include "muz/spacer/spacer_mbc.h"
#include "ast/rewriter/rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "ast/rewriter/th_rewriter.h"
#include "ast/scoped_proof.h"
#include "model/model_evaluator.h"
namespace spacer {
mbc::mbc(ast_manager &m) : m(m) {}
namespace {
class mbc_rewriter_cfg : public default_rewriter_cfg {
ast_manager &m;
const mbc::partition_map &m_pmap;
obj_map<expr,expr*> &m_subs;
model &m_mdl;
model_evaluator m_mev;
vector<expr_ref_vector> &m_parts;
unsigned m_current_part;
public:
mbc_rewriter_cfg(ast_manager &m, const mbc::partition_map &pmap,
obj_map<expr,expr*> &subs,
model &mdl, vector<expr_ref_vector> &parts) :
m(m), m_pmap(pmap), m_subs(subs), m_mdl(mdl), m_mev(m_mdl),
m_parts(parts), m_current_part(UINT_MAX)
{m_mev.set_model_completion(true);}
bool get_subst(expr *s, expr * & t, proof * & t_pr) {
if (!is_app(s)) return false;
unsigned part = UINT_MAX;
// not in partition map
if (!m_pmap.find (to_app(s)->get_decl(), part)) return false;
// first part element, remember it
if (!found_partition()) {
set_partition(part);
return false;
}
// already in our substitution map
expr *tmp = nullptr;
if (m_subs.find(s, tmp)) {
t = tmp;
return true;
}
// decide value based on model
expr_ref val(m);
// eval in the model
m_mev.eval(s, val, true);
// store decided equality (also keeps ref to s and val)
m_parts[part].push_back(m.mk_eq(s, val));
// store substitution
m_subs.insert(s, val);
t = val;
return true;
}
void reset() {reset_partition();};
void reset_partition() {m_current_part = UINT_MAX;}
unsigned partition() {return m_current_part;}
bool found_partition() {return m_current_part < UINT_MAX;}
void set_partition(unsigned v) {m_current_part = v;}
};
}
void mbc::operator()(const partition_map &pmap, expr_ref_vector &lits,
model &mdl, vector<expr_ref_vector> &res) {
scoped_no_proof _sp (m);
obj_map<expr,expr*> subs;
mbc_rewriter_cfg cfg(m, pmap, subs, mdl, res);
rewriter_tpl<mbc_rewriter_cfg> rw(m, false, cfg);
th_rewriter thrw(m);
for (auto *lit : lits) {
expr_ref new_lit(m);
rw.reset();
rw(lit, new_lit);
thrw(new_lit);
if (cfg.found_partition()) {
SASSERT(cfg.partition() < res.size());
res[cfg.partition()].push_back(new_lit);
}
}
TRACE("mbc", tout << "Input: " << lits << "\n"
<< "Output: \n";
for (auto &vec : res) tout << vec << "\n==================\n";);
}
}

45
src/muz/spacer/spacer_mbc.h Normal file
View file

@ -0,0 +1,45 @@
/*++
Copyright (c) 2018 Arie Gurfinkel
Module Name:
spacer_mbc.h
Abstract:
Model-Based Cartesian Decomposition
Author:
Arie Gurfinkel
Revision History:
--*/
#ifndef _SPACER_MBC_H_
#define _SPACER_MBC_H_
#include "ast/ast.h"
#include "util/obj_hashtable.h"
#include "model/model.h"
namespace spacer {
class mbc {
ast_manager &m;
public:
mbc(ast_manager &m);
typedef obj_map<func_decl, unsigned> partition_map;
/**
\Brief Model Based Cartesian projection of lits
*/
void operator()(const partition_map &pmap, expr_ref_vector &lits, model &mdl,
vector<expr_ref_vector> &res);
};
}
#endif

375
src/muz/spacer/spacer_pdr.cpp Normal file
View file

@ -0,0 +1,375 @@
/**++
Copyright (c) 2018 Arie Gurfinkel
Module Name:
spacer_pdr.h
Abstract:
SPACER gPDR strategy implementation
Author:
Arie Gurfinkel
Based on muz/pdr
Notes:
--*/
#include "muz/spacer/spacer_pdr.h"
#include "muz/base/dl_context.h"
#include "muz/spacer/spacer_mbc.h"
namespace spacer {
model_node::model_node(model_node* parent, class pob *pob):
m_pob(pob), m_parent(parent), m_next(nullptr), m_prev(nullptr),
m_orig_level(m_pob->level()), m_depth(0),
m_closed(false) {
SASSERT(m_pob);
if (m_parent) m_parent->add_child(this);
}
void model_node::add_child(model_node* kid) {
m_children.push_back(kid);
SASSERT(level() == kid->level() + 1);
SASSERT(level() > 0);
kid->m_depth = m_depth + 1;
if (is_closed()) set_open();
}
unsigned model_node::index_in_parent() const {
if (!m_parent) return 0;
for (unsigned i = 0, sz = m_parent->children().size(); i < sz; ++i) {
if (this == m_parent->children().get(i)) return i;
}
UNREACHABLE();
return 0;
}
void model_node::check_pre_closed() {
for (auto *kid : m_children) {if (kid->is_open()) return;}
set_pre_closed();
model_node* p = m_parent;
while (p && p->is_1closed()) {
p->set_pre_closed();
p = p->parent();
}
}
void model_node::set_open() {
SASSERT(m_closed);
m_closed = false;
model_node* p = parent();
while (p && p->is_closed()) {
p->m_closed = false;
p = p->parent();
}
}
void model_node::detach(model_node*& qhead) {
SASSERT(in_queue());
SASSERT(children().empty());
if (this == m_next) {
SASSERT(m_prev == this);
SASSERT(this == qhead);
qhead = nullptr;
}
else {
m_next->m_prev = m_prev;
m_prev->m_next = m_next;
if (this == qhead) qhead = m_next;
}
// detach
m_prev = nullptr;
m_next = nullptr;
}
// insert node n after this in the queue
// requires: this is in a queue or this == n
void model_node::insert_after(model_node* n) {
SASSERT(this == n || in_queue());
SASSERT(n);
SASSERT(!n->in_queue());
if (this == n) {
m_next = n;
m_prev = n;
}
else {
n->m_next = m_next;
m_next->m_prev = n;
m_next = n;
n->m_prev = this;
}
}
void model_search::reset() {
if (m_root) {
erase_children(*m_root, false);
remove_node(m_root, false);
dealloc(m_root);
m_root = nullptr;
}
m_cache.reset();
}
model_node* model_search::pop_front() {
model_node *res = m_qhead;
if (res) {
res->detach(m_qhead);
}
return res;
}
void model_search::add_leaf(model_node* _n) {
model_node& n = *_n;
SASSERT(n.children().empty());
model_nodes ns;
model_nodes& nodes = cache(n).insert_if_not_there2(n.post(), ns)->get_data().m_value;
if (nodes.contains(&n)) return;
nodes.push_back(_n);
if (nodes.size() == 1) {
SASSERT(n.is_open());
enqueue_leaf(n);
}
else {
n.set_pre_closed();
}
}
void model_search::enqueue_leaf(model_node& n) {
SASSERT(n.is_open());
SASSERT(!n.in_queue());
// queue is empty, initialize it with n
if (!m_qhead) {
m_qhead = &n;
m_qhead->insert_after(m_qhead);
}
// insert n after m_qhead
else if (m_bfs) {
m_qhead->insert_after(&n);
}
// insert n after m_qhead()->next()
else {
m_qhead->next()->insert_after(&n);
}
}
void model_search::set_root(model_node* root) {
reset();
m_root = root;
SASSERT(m_root);
SASSERT(m_root->children().empty());
add_leaf(root);
}
void model_search::backtrack_level(bool uses_level, model_node& n) {
SASSERT(m_root);
if (uses_level) {NOT_IMPLEMENTED_YET();}
if (uses_level && m_root->level() > n.level()) {
n.increase_level();
enqueue_leaf(n);
}
else {
model_node* p = n.parent();
if (p) {
erase_children(*p, true);
enqueue_leaf(*p);
}
}
}
obj_map<expr, ptr_vector<model_node> >& model_search::cache(model_node const& n) {
unsigned l = n.orig_level();
if (l >= m_cache.size()) m_cache.resize(l + 1);
return m_cache[l];
}
void model_search::erase_children(model_node& n, bool backtrack) {
ptr_vector<model_node> todo, nodes;
todo.append(n.children());
// detach n from queue
if (n.in_queue()) n.detach(m_qhead);
n.reset_children();
while (!todo.empty()) {
model_node* m = todo.back();
todo.pop_back();
nodes.push_back(m);
todo.append(m->children());
remove_node(m, backtrack);
}
std::for_each(nodes.begin(), nodes.end(), delete_proc<model_node>());
}
// removes node from the search tree and from the cache
void model_search::remove_node(model_node* _n, bool backtrack) {
model_node& n = *_n;
model_nodes& nodes = cache(n).find(n.post());
nodes.erase(_n);
if (n.in_queue()) n.detach(m_qhead);
// TBD: siblings would also fail if n is not a goal.
if (!nodes.empty() && backtrack &&
nodes[0]->children().empty() && nodes[0]->is_closed()) {
model_node* n1 = nodes[0];
n1->set_open();
enqueue_leaf(*n1);
}
if (nodes.empty()) cache(n).remove(n.post());
}
lbool context::gpdr_solve_core() {
scoped_watch _w_(m_solve_watch);
//if there is no query predicate, abort
if (!m_rels.find(m_query_pred, m_query)) { return l_false; }
model_search ms(m_pdr_bfs);
unsigned lvl = 0;
unsigned max_level = m_max_level;
for (lvl = 0; lvl < max_level; ++lvl) {
checkpoint();
IF_VERBOSE(1,verbose_stream() << "GPDR Entering level "<< lvl << "\n";);
STRACE("spacer.expand-add", tout << "\n* LEVEL " << lvl << "\n";);
m_expanded_lvl = infty_level();
m_stats.m_max_query_lvl = lvl;
if (gpdr_check_reachability(lvl, ms)) {return l_true;}
if (lvl > 0) {
if (propagate(m_expanded_lvl, lvl, UINT_MAX)) {return l_false;}
}
}
// communicate failure to datalog::context
if (m_context) {
m_context->set_status(datalog::BOUNDED);
}
return l_undef;
}
bool context::gpdr_check_reachability(unsigned lvl, model_search &ms) {
pob_ref root_pob = m_query->mk_pob(nullptr, lvl, 0, m.mk_true());
model_node *root_node = alloc(model_node, nullptr, root_pob.get());
ms.set_root(root_node);
pob_ref_buffer new_pobs;
while (model_node *node = ms.pop_front()) {
IF_VERBOSE(2, verbose_stream() << "Expand node: "
<< node->level() << "\n";);
new_pobs.reset();
checkpoint();
pred_transformer &pt = node->pt();
// check reachable cache
if (pt.is_must_reachable(node->pob()->post(), nullptr)) {
TRACE("spacer",
tout << "must-reachable: " << pt.head()->get_name() << " level: "
<< node->level() << " depth: " << node->depth () << "\n";
tout << mk_pp(node->pob()->post(), m) << "\n";);
node->set_closed();
if (node == root_node) return true;
continue;
}
switch (expand_pob(*node->pob(), new_pobs)){
case l_true:
node->set_closed();
if (node == root_node) return true;
break;
case l_false:
ms.backtrack_level(false, *node);
if (node == root_node) return false;
break;
case l_undef:
SASSERT(!new_pobs.empty());
for (auto pob : new_pobs) {
TRACE("spacer_pdr",
tout << "looking at pob at level " << pob->level() << " "
<< mk_pp(pob->post(), m) << "\n";);
if (pob != node->pob())
ms.add_leaf(alloc(model_node, node, pob));
}
node->check_pre_closed();
break;
}
}
return root_node->is_closed();
}
bool context::gpdr_create_split_children(pob &n, const datalog::rule &r,
expr *trans,
model_ref &mdl,
pob_ref_buffer &out) {
pred_transformer &pt = n.pt();
ptr_vector<func_decl> preds;
pt.find_predecessors(r, preds);
SASSERT(preds.size() > 1);
ptr_vector<pred_transformer> ppts;
for (auto *p : preds) ppts.push_back(&get_pred_transformer(p));
mbc::partition_map pmap;
for (unsigned i = 0, sz = preds.size(); i < sz; ++i) {
func_decl *p = preds.get(i);
pred_transformer &ppt = *ppts.get(i);
for (unsigned j = 0, jsz = p->get_arity(); j < jsz; ++j) {
pmap.insert(m_pm.o2o(ppt.sig(j), 0, i), i);
}
}
spacer::mbc _mbc(m);
expr_ref_vector lits(m);
flatten_and(trans, lits);
vector<expr_ref_vector> res(preds.size(), expr_ref_vector(m));
_mbc(pmap, lits, *mdl.get(), res);
// pick an order to process children
unsigned_vector kid_order;
kid_order.resize(preds.size(), 0);
for (unsigned i = 0, sz = preds.size(); i < sz; ++i) kid_order[i] = i;
if (m_children_order == CO_REV_RULE) {
kid_order.reverse();
}
else if (m_children_order == CO_RANDOM) {
shuffle(kid_order.size(), kid_order.c_ptr(), m_random);
}
for (unsigned i = 0, sz = res.size(); i < sz; ++i) {
unsigned j = kid_order[i];
expr_ref post(m);
pred_transformer &ppt = *ppts.get(j);
post = mk_and(res.get(j));
m_pm.formula_o2n(post.get(), post, j, true);
pob * k = ppt.mk_pob(&n, prev_level(n.level()), n.depth(), post);
out.push_back(k);
IF_VERBOSE (1, verbose_stream()
<< "\n\tcreate_child: " << k->pt().head()->get_name()
<< " (" << k->level() << ", " << k->depth() << ") "
<< (k->use_farkas_generalizer() ? "FAR " : "SUB ")
<< k->post()->get_id();
verbose_stream().flush(););
TRACE ("spacer",
tout << "create-pob: " << k->pt().head()->get_name()
<< " level: " << k->level()
<< " depth: " << k->depth ()
<< " fvsz: " << k->get_free_vars_size() << "\n"
<< mk_pp(k->post(), m) << "\n";);
}
return true;
}
} // spacer

107
src/muz/spacer/spacer_pdr.h Normal file
View file

@ -0,0 +1,107 @@
/**++
Copyright (c) 2018 Arie Gurfinkel
Module Name:
spacer_pdr.h
Abstract:
SPACER gPDR strategy implementation
Author:
Arie Gurfinkel
Based on muz/pdr
Notes:
--*/
#ifndef _SPACER_PDR_H_
#define _SPACER_PDR_H_
#include "muz/spacer/spacer_context.h"
namespace spacer {
// structure for counter-example search.
class model_node {
pob_ref m_pob; // proof obligation
model_node* m_parent; // parent in the search tree
ptr_vector<model_node> m_children; // children in the search tree
model_node* m_next; // next element of an in-place circular queue
model_node* m_prev; // prev element of an in-place circular queue
unsigned m_orig_level; // level at which this search node was created
unsigned m_depth; //
bool m_closed; // whether the pob is derivable
public:
model_node(model_node* parent, pob* pob);
void add_child(model_node* kid);
expr *post() const { return m_pob->post(); }
unsigned level() const { return m_pob->level(); }
unsigned orig_level() const { return m_orig_level; }
unsigned depth() const { return m_depth; }
void increase_level() { m_pob->inc_level(); }
pob_ref &pob() { return m_pob; }
ptr_vector<model_node> const& children() { return m_children; }
pred_transformer& pt() const { return m_pob->pt(); }
model_node* parent() const { return m_parent; }
// order in children of the parent
unsigned index_in_parent() const;
bool is_closed() const { return m_closed; }
bool is_open() const { return !is_closed(); }
// closed or has children and they are all closed
bool is_1closed() {
if (is_closed()) return true;
if (m_children.empty()) return false;
for (auto kid : m_children)
if (kid->is_open()) return false;
return true;
}
void check_pre_closed();
void set_pre_closed() { m_closed = true; }
void set_closed() { m_closed = true; }
void set_open();
void reset_children() { m_children.reset(); }
/// queue
// remove this node from the given queue
void detach(model_node*& qhead);
void insert_after(model_node* n);
model_node* next() const { return m_next; }
bool in_queue() { return m_next && m_prev; }
};
class model_search {
typedef ptr_vector<model_node> model_nodes;
bool m_bfs;
model_node* m_root;
model_node* m_qhead;
vector<obj_map<expr, model_nodes > > m_cache;
obj_map<expr, model_nodes>& cache(model_node const& n);
void erase_children(model_node& n, bool backtrack);
void remove_node(model_node* _n, bool backtrack);
public:
model_search(bool bfs): m_bfs(bfs), m_root(nullptr), m_qhead(nullptr) {}
~model_search() {reset();}
void set_root(model_node* n);
void reset();
model_node* pop_front();
void add_leaf(model_node* n); // add fresh node.
model_node& get_root() const { return *m_root; }
void backtrack_level(bool uses_level, model_node& n);
void remove_goal(model_node& n);
void enqueue_leaf(model_node &n);
};
}
#endif

555
src/muz/spacer/spacer_proof_utils.cpp Normal file
View file

@ -0,0 +1,555 @@
/*++
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_proof_utils.cpp
Abstract:
Utilities to traverse and manipulate proofs
Author:
Bernhard Gleiss
Arie Gurfinkel
Revision History:
--*/
#include "util/params.h"
#include "ast/ast_pp.h"
#include "ast/ast_util.h"
#include "ast/proofs/proof_checker.h"
#include "muz/base/dl_util.h"
#include "muz/spacer/spacer_iuc_proof.h"
#include "ast/proofs/proof_utils.h"
#include "muz/spacer/spacer_proof_utils.h"
#include "muz/spacer/spacer_util.h"
namespace spacer {
// arithmetic lemma recognizer
bool is_arith_lemma(ast_manager& m, proof* pr)
{
// arith lemmas: second parameter specifies exact type of lemma,
// could be "farkas", "triangle-eq", "eq-propagate",
// "assign-bounds", maybe also something else
if (pr->get_decl_kind() == PR_TH_LEMMA) {
func_decl* d = pr->get_decl();
symbol sym;
return d->get_num_parameters() >= 1 &&
d->get_parameter(0).is_symbol(sym) &&
sym == "arith";
}
return false;
}
// farkas lemma recognizer
bool is_farkas_lemma(ast_manager& m, proof* pr)
{
if (pr->get_decl_kind() == PR_TH_LEMMA)
{
func_decl* d = pr->get_decl();
symbol sym;
return d->get_num_parameters() >= 2 &&
d->get_parameter(0).is_symbol(sym) && sym == "arith" &&
d->get_parameter(1).is_symbol(sym) && sym == "farkas";
}
return false;
}
/*
* ====================================
* methods for transforming proofs
* ====================================
*/
void theory_axiom_reducer::reset() {
m_cache.reset();
m_pinned.reset();
}
// -- rewrite theory axioms into theory lemmas
proof_ref theory_axiom_reducer::reduce(proof* pr) {
proof_post_order pit(pr, m);
while (pit.hasNext()) {
proof* p = pit.next();
if (m.get_num_parents(p) == 0 && is_arith_lemma(m, p)) {
// we have an arith-theory-axiom and want to get rid of it
// we need to replace the axiom with
// (a) corresponding hypothesis,
// (b) a theory lemma, and
// (c) a lemma.
// Furthermore update data-structures
app *fact = to_app(m.get_fact(p));
ptr_buffer<expr> cls;
if (m.is_or(fact)) {
for (unsigned i = 0, sz = fact->get_num_args(); i < sz; ++i)
cls.push_back(fact->get_arg(i));
}
else
cls.push_back(fact);
// (a) create hypothesis
ptr_buffer<proof> hyps;
for (unsigned i = 0, sz = cls.size(); i < sz; ++i) {
expr *c;
expr_ref hyp_fact(m);
if (m.is_not(cls[i], c))
hyp_fact = c;
else
hyp_fact = m.mk_not (cls[i]);
proof* hyp = m.mk_hypothesis(hyp_fact);
m_pinned.push_back(hyp);
hyps.push_back(hyp);
}
// (b) create farkas lemma. Rebuild parameters since
// mk_th_lemma() adds tid as first parameter
unsigned num_params = p->get_decl()->get_num_parameters();
parameter const* params = p->get_decl()->get_parameters();
vector<parameter> parameters;
for (unsigned i = 1; i < num_params; ++i) parameters.push_back(params[i]);
SASSERT(params[0].is_symbol());
family_id tid = m.mk_family_id(params[0].get_symbol());
SASSERT(tid != null_family_id);
proof* th_lemma = m.mk_th_lemma(tid, m.mk_false(),
hyps.size(), hyps.c_ptr(),
num_params-1, parameters.c_ptr());
m_pinned.push_back(th_lemma);
SASSERT(is_arith_lemma(m, th_lemma));
// (c) create lemma
proof* res = m.mk_lemma(th_lemma, fact);
m_pinned.push_back(res);
m_cache.insert(p, res);
SASSERT(m.get_fact(res) == m.get_fact(p));
}
else {
// proof is dirty, if a sub-proof of one of its premises
// has been transformed
bool dirty = false;
ptr_buffer<expr> args;
for (unsigned i = 0, sz = m.get_num_parents(p); i < sz; ++i) {
proof *pp, *tmp;
pp = m.get_parent(p, i);
VERIFY(m_cache.find(pp, tmp));
args.push_back(tmp);
dirty |= (pp != tmp);
}
// if not dirty just use the old step
if (!dirty) m_cache.insert(p, p);
// otherwise create new proof with the corresponding proofs
// of the premises
else {
if (m.has_fact(p)) args.push_back(m.get_fact(p));
SASSERT(p->get_decl()->get_arity() == args.size());
proof* res = m.mk_app(p->get_decl(),
args.size(), (expr * const*)args.c_ptr());
m_pinned.push_back(res);
m_cache.insert(p, res);
}
}
}
proof* res;
VERIFY(m_cache.find(pr,res));
DEBUG_CODE(
proof_checker pc(m);
expr_ref_vector side(m);
SASSERT(pc.check(res, side));
);
return proof_ref(res, m);
}
/* ------------------------------------------------------------------------- */
/* hypothesis_reducer */
/* ------------------------------------------------------------------------- */
proof_ref hypothesis_reducer::reduce(proof* pr) {
compute_hypsets(pr);
collect_units(pr);
proof_ref res(reduce_core(pr), m);
SASSERT(res);
reset();
DEBUG_CODE(proof_checker pc(m);
expr_ref_vector side(m);
SASSERT(pc.check(res, side)););
return res;
}
void hypothesis_reducer::reset() {
m_active_hyps.reset();
m_units.reset();
m_cache.reset();
for (auto t : m_pinned_active_hyps) dealloc(t);
m_pinned_active_hyps.reset();
m_pinned.reset();
m_hyp_mark.reset();
m_open_mark.reset();
m_visited.reset();
}
void hypothesis_reducer::compute_hypsets(proof *pr) {
ptr_buffer<proof> todo;
todo.push_back(pr);
while (!todo.empty()) {
proof* p = todo.back();
if (m_visited.is_marked(p)) {
todo.pop_back();
continue;
}
unsigned todo_sz = todo.size();
for (unsigned i = 0, sz = m.get_num_parents(p); i < sz; ++i) {
SASSERT(m.is_proof(p->get_arg(i)));
proof *parent = to_app(p->get_arg(i));
if (!m_visited.is_marked(parent))
todo.push_back(parent);
}
if (todo.size() > todo_sz) continue;
todo.pop_back();
m_visited.mark(p);
proof_ptr_vector* active_hyps = nullptr;
// fill both sets
if (m.is_hypothesis(p)) {
// create active_hyps-set for step p
proof_ptr_vector* active_hyps = alloc(proof_ptr_vector);
m_pinned_active_hyps.insert(active_hyps);
m_active_hyps.insert(p, active_hyps);
active_hyps->push_back(p);
m_open_mark.mark(p);
m_hyp_mark.mark(m.get_fact(p));
continue;
}
ast_fast_mark1 seen;
active_hyps = alloc(proof_ptr_vector);
for (unsigned i = 0, sz = m.get_num_parents(p); i < sz; ++i) {
proof* parent = m.get_parent(p, i);
// lemmas clear all hypotheses above them
if (m.is_lemma(p)) continue;
for (auto *x : *m_active_hyps.find(parent)) {
if (!seen.is_marked(x)) {
seen.mark(x);
active_hyps->push_back(x);
m_open_mark.mark(p);
}
}
}
if (active_hyps->empty()) {
dealloc(active_hyps);
m_active_hyps.insert(p, &m_empty_vector);
}
else {
m_pinned_active_hyps.push_back(active_hyps);
m_active_hyps.insert(p, active_hyps);
}
}
}
// collect all units that are hyp-free and are used as hypotheses somewhere
// requires that m_active_hyps has been computed
void hypothesis_reducer::collect_units(proof* pr) {
proof_post_order pit(pr, m);
while (pit.hasNext()) {
proof* p = pit.next();
if (!m.is_hypothesis(p)) {
// collect units that are hyp-free and are used as
// hypotheses in the proof pr
if (!m_open_mark.is_marked(p) && m.has_fact(p) &&
m_hyp_mark.is_marked(m.get_fact(p)))
m_units.insert(m.get_fact(p), p);
}
}
}
/**
\brief returns true if p is an ancestor of q
*/
bool hypothesis_reducer::is_ancestor(proof *p, proof *q) {
if (p == q) return true;
ptr_vector<proof> todo;
todo.push_back(q);
expr_mark visited;
while (!todo.empty()) {
proof *cur;
cur = todo.back();
todo.pop_back();
if (visited.is_marked(cur)) continue;
if (cur == p) return true;
visited.mark(cur);
for (unsigned i = 0, sz = m.get_num_parents(cur); i < sz; ++i) {
todo.push_back(m.get_parent(cur, i));
}
}
return false;
}
proof* hypothesis_reducer::reduce_core(proof* pf) {
SASSERT(m.is_false(m.get_fact(pf)));
proof *res = NULL;
ptr_vector<proof> todo;
todo.push_back(pf);
ptr_buffer<proof> args;
bool dirty = false;
while (true) {
proof *p, *tmp, *pp;
unsigned todo_sz;
p = todo.back();
if (m_cache.find(p, tmp)) {
todo.pop_back();
continue;
}
dirty = false;
args.reset();
todo_sz = todo.size();
for (unsigned i = 0, sz = m.get_num_parents(p); i < sz; ++i) {
pp = m.get_parent(p, i);
if (m_cache.find(pp, tmp)) {
args.push_back(tmp);
dirty |= pp != tmp;
} else {
todo.push_back(pp);
}
}
if (todo_sz < todo.size()) continue;
todo.pop_back();
// transform the current proof node
if (m.is_hypothesis(p)) {
// if possible, replace a hypothesis by a unit derivation
if (m_units.find(m.get_fact(p), tmp)) {
// use already transformed proof of the unit if it is available
proof* proof_of_unit;
if (!m_cache.find(tmp, proof_of_unit)) {
proof_of_unit = tmp;
}
// make sure hypsets for the unit are computed
// AG: is this needed?
compute_hypsets(proof_of_unit);
// if the transformation doesn't create a cycle, perform it
if (!is_ancestor(p, proof_of_unit)) {
res = proof_of_unit;
}
else {
// -- failed to transform the proof, perhaps bad
// -- choice of the proof of unit
res = p;
}
}
else {
// -- no unit found to replace the hypothesis
res = p;
}
}
else if (!dirty) {res = p;}
else if (m.is_lemma(p)) {
// lemma: reduce the premise; remove reduced consequences
// from conclusion
SASSERT(args.size() == 1);
res = mk_lemma_core(args[0], m.get_fact(p));
// -- re-compute hypsets
compute_hypsets(res);
}
else if (m.is_unit_resolution(p)) {
// unit: reduce untis; reduce the first premise; rebuild
// unit resolution
res = mk_unit_resolution_core(p, args);
// -- re-compute hypsets
compute_hypsets(res);
}
else {
res = mk_proof_core(p, args);
// -- re-compute hypsets
compute_hypsets(res);
}
SASSERT(res);
m_cache.insert(p, res);
// bail out as soon as found a sub-proof of false
if (!m_open_mark.is_marked(res) && m.has_fact(res) && m.is_false(m.get_fact(res)))
return res;
}
UNREACHABLE();
return nullptr;
}
proof* hypothesis_reducer::mk_lemma_core(proof* premise, expr *fact) {
SASSERT(m.is_false(m.get_fact(premise)));
SASSERT(m_active_hyps.contains(premise));
proof_ptr_vector* active_hyps = m_active_hyps.find(premise);
// if there is no active hypothesis return the premise
if (!m_open_mark.is_marked(premise)) {
// XXX just in case premise might go away
m_pinned.push_back(premise);
return premise;
}
// add some stability
std::stable_sort(active_hyps->begin(), active_hyps->end(), ast_lt_proc());
// otherwise, build a disjunction of the negated active hypotheses
// and add a lemma proof step
expr_ref_buffer args(m);
for (auto hyp : *active_hyps) {
expr *hyp_fact, *t;
hyp_fact = m.get_fact(hyp);
if (m.is_not(hyp_fact, t))
args.push_back(t);
else
args.push_back(m.mk_not(hyp_fact));
}
expr_ref lemma(m);
lemma = mk_or(m, args.size(), args.c_ptr());
proof* res;
res = m.mk_lemma(premise, lemma);
m_pinned.push_back(res);
return res;
}
proof* hypothesis_reducer::mk_unit_resolution_core(proof *ures,
ptr_buffer<proof>& args) {
// if any literal is false, we don't need a unit resolution step
// This can be the case due to some previous transformations
for (unsigned i = 1, sz = args.size(); i < sz; ++i) {
if (m.is_false(m.get_fact(args[i]))) {
// XXX pin just in case
m_pinned.push_back(args[i]);
return args[i];
}
}
proof* arg0 = args[0];
app *fact0 = to_app(m.get_fact(arg0));
ptr_buffer<proof> pf_args;
ptr_buffer<expr> pf_fact;
pf_args.push_back(arg0);
// compute literals to be resolved
ptr_buffer<expr> lits;
// fact0 is a literal whenever the original resolution was a
// binary resolution to an empty clause
if (m.get_num_parents(ures) == 2 && m.is_false(m.get_fact(ures))) {
lits.push_back(fact0);
}
// fact0 is a literal unless it is a dijsunction
else if (!m.is_or(fact0)) {
lits.push_back(fact0);
}
// fact0 is a literal only if it appears as a literal in the
// original resolution
else {
lits.reset();
app* ures_fact = to_app(m.get_fact(m.get_parent(ures, 0)));
for (unsigned i = 0, sz = ures_fact->get_num_args(); i < sz; ++i) {
if (ures_fact->get_arg(i) == fact0) {
lits.push_back(fact0);
break;
}
}
if (lits.empty()) {
lits.append(fact0->get_num_args(), fact0->get_args());
}
}
// -- find all literals that are resolved on
for (unsigned i = 0, sz = lits.size(); i < sz; ++i) {
bool found = false;
for (unsigned j = 1; j < args.size(); ++j) {
if (m.is_complement(lits.get(i), m.get_fact(args[j]))) {
found = true;
pf_args.push_back(args[j]);
break;
}
}
if (!found) {pf_fact.push_back(lits.get(i));}
}
// unit resolution got reduced to noop
if (pf_args.size() == 1) {
// XXX pin just in case
m_pinned.push_back(arg0);
return arg0;
}
// make unit resolution proof step
// expr_ref tmp(m);
// tmp = mk_or(m, pf_fact.size(), pf_fact.c_ptr());
// proof* res = m.mk_unit_resolution(pf_args.size(), pf_args.c_ptr(), tmp);
proof *res = m.mk_unit_resolution(pf_args.size(), pf_args.c_ptr());
m_pinned.push_back(res);
return res;
}
proof* hypothesis_reducer::mk_proof_core(proof* old, ptr_buffer<proof>& args) {
// if any of the literals are false, we don't need a step
for (unsigned i = 0; i < args.size(); ++i) {
if (m.is_false(m.get_fact(args[i]))) {
// XXX just in case
m_pinned.push_back(args[i]);
return args[i];
}
}
// otherwise build step
// BUG: I guess this doesn't work with quantifiers (since they are no apps)
args.push_back(to_app(m.get_fact(old)));
SASSERT(old->get_decl()->get_arity() == args.size());
proof* res = m.mk_app(old->get_decl(), args.size(),
(expr * const*)args.c_ptr());
m_pinned.push_back(res);
return res;
}
};

105
src/muz/spacer/spacer_proof_utils.h Normal file
View file

@ -0,0 +1,105 @@
/*++
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_proof_utils.cpp
Abstract:
Utilities to traverse and manipulate proofs
Author:
Bernhard Gleiss
Arie Gurfinkel
Revision History:
--*/
#ifndef _SPACER_PROOF_UTILS_H_
#define _SPACER_PROOF_UTILS_H_
#include "ast/ast.h"
namespace spacer {
bool is_arith_lemma(ast_manager& m, proof* pr);
bool is_farkas_lemma(ast_manager& m, proof* pr);
/// rewrites theory axioms into theory lemmas
class theory_axiom_reducer {
public:
theory_axiom_reducer(ast_manager& m) : m(m), m_pinned(m) {}
// reduce theory axioms and return transformed proof
proof_ref reduce(proof* pr);
private:
ast_manager &m;
// tracking all created expressions
expr_ref_vector m_pinned;
// maps each proof of a clause to the transformed subproof of
// that clause
obj_map<proof, proof*> m_cache;
void reset();
};
/// reduces the number of hypotheses in a proof
class hypothesis_reducer
{
public:
hypothesis_reducer(ast_manager &m) : m(m), m_pinned(m) {}
~hypothesis_reducer() {reset();}
// reduce hypothesis and return transformed proof
proof_ref reduce(proof* pf);
private:
typedef ptr_vector<proof> proof_ptr_vector;
ast_manager &m;
proof_ptr_vector m_empty_vector;
// created expressions
expr_ref_vector m_pinned;
// created sets of active hypothesis
ptr_vector<proof_ptr_vector> m_pinned_active_hyps;
// maps a proof to the transformed proof
obj_map<proof, proof*> m_cache;
// maps a unit literal to its derivation
obj_map<expr, proof*> m_units;
// maps a proof node to the set of its active (i.e., in scope) hypotheses
obj_map<proof, proof_ptr_vector*> m_active_hyps;
/// marks if an expression is ever used as a hypothesis in a proof
expr_mark m_hyp_mark;
/// marks a proof as open, i.e., has a non-discharged hypothesis as ancestor
expr_mark m_open_mark;
expr_mark m_visited;
void reset();
/// true if p is an ancestor of q
bool is_ancestor(proof *p, proof *q);
// compute active_hyps and parent_hyps for a given proof node and
// all its ancestors
void compute_hypsets(proof* pr);
// compute m_units
void collect_units(proof* pr);
// -- rewrite proof to reduce number of hypotheses used
proof* reduce_core(proof* pf);
proof* mk_lemma_core(proof *pf, expr *fact);
proof* mk_unit_resolution_core(proof* ures, ptr_buffer<proof>& args);
proof* mk_proof_core(proof* old, ptr_buffer<proof>& args);
};
}
#endif

175
src/muz/spacer/spacer_prop_solver.cpp
View file

@ -35,13 +35,15 @@ Revision History:
#include "muz/spacer/spacer_farkas_learner.h"
#include "muz/spacer/spacer_prop_solver.h"
#include "muz/base/fixedpoint_params.hpp"
#include "model/model_evaluator.h"
#include "muz/base/fp_params.hpp"
namespace spacer {
prop_solver::prop_solver(manager& pm, fixedpoint_params const& p, symbol const& name) :
m(pm.get_manager()),
m_pm(pm),
prop_solver::prop_solver(ast_manager &m,
solver *solver0, solver *solver1,
fp_params const& p, symbol const& name) :
m(m),
m_name(name),
m_ctx(nullptr),
m_pos_level_atoms(m),
@ -54,17 +56,21 @@ prop_solver::prop_solver(manager& pm, fixedpoint_params const& p, symbol const&
m_use_push_bg(p.spacer_keep_proxy())
{
m_solvers[0] = pm.mk_fresh();
m_fparams[0] = &pm.fparams();
m_solvers[0] = solver0;
m_solvers[1] = solver1;
m_solvers[1] = pm.mk_fresh2();
m_fparams[1] = &pm.fparams2();
m_contexts[0] = alloc(spacer::itp_solver, *(m_solvers[0]), p.spacer_new_unsat_core(), p.spacer_minimize_unsat_core(), p.spacer_farkas_optimized(), p.spacer_farkas_a_const(), p.spacer_split_farkas_literals());
m_contexts[1] = alloc(spacer::itp_solver, *(m_solvers[1]), p.spacer_new_unsat_core(), p.spacer_minimize_unsat_core(), p.spacer_farkas_optimized(), p.spacer_farkas_a_const(), p.spacer_split_farkas_literals());
for (unsigned i = 0; i < 2; ++i)
{ m_contexts[i]->assert_expr(m_pm.get_background()); }
m_contexts[0] = alloc(spacer::iuc_solver, *(m_solvers[0]),
p.spacer_iuc(),
p.spacer_iuc_arith(),
p.spacer_iuc_print_farkas_stats(),
p.spacer_iuc_old_hyp_reducer(),
p.spacer_iuc_split_farkas_literals());
m_contexts[1] = alloc(spacer::iuc_solver, *(m_solvers[1]),
p.spacer_iuc(),
p.spacer_iuc_arith(),
p.spacer_iuc_print_farkas_stats(),
p.spacer_iuc_old_hyp_reducer(),
p.spacer_iuc_split_farkas_literals());
}
void prop_solver::add_level()
@ -119,6 +125,8 @@ void prop_solver::assert_expr(expr * form)
void prop_solver::assert_expr(expr * form, unsigned level)
{
if (is_infty_level(level)) {assert_expr(form);return;}
ensure_level(level);
app * lev_atom = m_pos_level_atoms[level].get();
app_ref lform(m.mk_or(form, lev_atom), m);
@ -126,18 +134,109 @@ void prop_solver::assert_expr(expr * form, unsigned level)
}
/// Local model guided maxsmt
lbool prop_solver::mss(expr_ref_vector &hard, expr_ref_vector &soft) {
// replace expressions by assumption literals
iuc_solver::scoped_mk_proxy _p_(*m_ctx, hard);
unsigned hard_sz = hard.size();
lbool res = m_ctx->check_sat(hard.size(), hard.c_ptr());
// bail out if hard constraints are not sat, or if there are no
// soft constraints
if (res != l_true || soft.empty()) {return res;}
// the main loop
model_ref mdl;
m_ctx->get_model(mdl);
// don't proxy soft literals. Assume that they are propositional.
hard.append(soft);
soft.reset();
// hard is divided into 4 regions
// x < hard_sz ---> hard constraints
// hard_sz <= x < i ---> sat soft constraints
// i <= x < j ---> backbones (unsat soft constraints)
// j <= x < hard.size() ---> unprocessed soft constraints
unsigned i, j;
i = hard_sz;
j = hard_sz;
while (j < hard.size()) {
model_evaluator mev(*mdl);
// move all true soft constraints to [hard_sz, i)
for (unsigned k = j; k < hard.size(); ++k) {
expr_ref e(m);
e = hard.get(k);
if (!mev.is_false(e) /* true or unset */) {
expr_ref tmp(m);
tmp = hard.get(i);
hard[i] = e;
if (i < j) {
// tmp is a backbone, put it at j
if (j == k) {hard[j] = tmp;}
else /* j < k */ {
e = hard.get(j);
hard[j] = tmp;
hard[k] = e;
}
j++;
}
else {
// there are no backbone literals
hard[k] = tmp;
j++;
}
i++;
}
}
// done with the model. Reset to avoid confusion in debugging
mdl.reset();
// -- grow the set of backbone literals
for (;j < hard.size(); ++j) {
res = m_ctx->check_sat(j+1, hard.c_ptr());
if (res == l_false) {
// -- flip non-true literal to be false
hard[j] = mk_not(m, hard.get(j));
}
else if (res == l_true) {
// -- get the model for the next iteration of the outer loop
m_ctx->get_model(mdl);
break;
}
else if (res == l_undef) {
// -- conservatively bail out
hard.resize(hard_sz);
return l_undef;
}
}
}
// move sat soft constraints to the output vector
for (unsigned k = i; k < j; ++k) { soft.push_back(hard.get(k)); }
// cleanup hard constraints
hard.resize(hard_sz);
return l_true;
}
/// Poor man's maxsat. No guarantees of maximum solution
/// Runs maxsat loop on m_ctx Returns l_false if hard is unsat,
/// otherwise reduces soft such that hard & soft is sat.
lbool prop_solver::maxsmt(expr_ref_vector &hard, expr_ref_vector &soft)
lbool prop_solver::maxsmt(expr_ref_vector &hard, expr_ref_vector &soft,
vector<expr_ref_vector> const & clauses)
{
// replace expressions by assumption literals
itp_solver::scoped_mk_proxy _p_(*m_ctx, hard);
iuc_solver::scoped_mk_proxy _p_(*m_ctx, hard);
unsigned hard_sz = hard.size();
// assume soft constraints are propositional literals (no need to proxy)
hard.append(soft);
lbool res = m_ctx->check_sat(hard.size(), hard.c_ptr());
lbool res = m_ctx->check_sat_cc(hard, clauses);
// if hard constraints alone are unsat or there are no soft
// constraints, we are done
if (res != l_false || soft.empty()) { return res; }
@ -146,7 +245,7 @@ lbool prop_solver::maxsmt(expr_ref_vector &hard, expr_ref_vector &soft)
soft.reset();
expr_ref saved(m);
ptr_vector<expr> core;
expr_ref_vector core(m);
m_ctx->get_unsat_core(core);
// while there are soft constraints
@ -171,7 +270,7 @@ lbool prop_solver::maxsmt(expr_ref_vector &hard, expr_ref_vector &soft)
}
// check that the NEW constraints became sat
res = m_ctx->check_sat(hard.size(), hard.c_ptr());
res = m_ctx->check_sat_cc(hard, clauses);
if (res != l_false) { break; }
// still unsat, update the core and repeat
core.reset();
@ -189,17 +288,21 @@ lbool prop_solver::maxsmt(expr_ref_vector &hard, expr_ref_vector &soft)
return res;
}
lbool prop_solver::internal_check_assumptions(
expr_ref_vector& hard_atoms,
expr_ref_vector& soft_atoms)
lbool prop_solver::internal_check_assumptions(expr_ref_vector &hard_atoms,
expr_ref_vector &soft_atoms,
vector<expr_ref_vector> const & clauses)
{
// XXX Turn model generation if m_model != 0
SASSERT(m_ctx);
SASSERT(m_ctx_fparams);
flet<bool> _model(m_ctx_fparams->m_model, m_model != nullptr);
params_ref p;
if (m_model != nullptr) {
p.set_bool("produce_models", true);
m_ctx->updt_params(p);
}
if (m_in_level) { assert_level_atoms(m_current_level); }
lbool result = maxsmt(hard_atoms, soft_atoms);
lbool result = maxsmt(hard_atoms, soft_atoms, clauses);
if (result != l_false && m_model) { m_ctx->get_model(*m_model); }
SASSERT(result != l_false || soft_atoms.empty());
@ -226,15 +329,22 @@ lbool prop_solver::internal_check_assumptions(
}
if (result == l_false && m_core && m.proofs_enabled() && !m_subset_based_core) {
TRACE("spacer", tout << "theory core\n";);
TRACE("spacer", tout << "Using IUC core\n";);
m_core->reset();
m_ctx->get_itp_core(*m_core);
m_ctx->get_iuc(*m_core);
} else if (result == l_false && m_core) {
m_core->reset();
m_ctx->get_unsat_core(*m_core);
// manually undo proxies because maxsmt() call above manually adds proxies
// AG: don't think this is needed. maxsmt() undoes the proxies already
m_ctx->undo_proxies(*m_core);
}
if (m_model != nullptr) {
p.set_bool("produce_models", false);
m_ctx->updt_params(p);
}
return result;
}
@ -242,9 +352,11 @@ lbool prop_solver::internal_check_assumptions(
lbool prop_solver::check_assumptions(const expr_ref_vector & _hard,
expr_ref_vector& soft,
const expr_ref_vector &clause,
unsigned num_bg, expr * const * bg,
unsigned solver_id)
{
expr_ref cls(m);
// current clients expect that flattening of HARD is
// done implicitly during check_assumptions
expr_ref_vector hard(m);
@ -252,12 +364,11 @@ lbool prop_solver::check_assumptions(const expr_ref_vector & _hard,
flatten_and(hard);
m_ctx = m_contexts [solver_id == 0 ? 0 : 0 /* 1 */].get();
m_ctx_fparams = m_fparams [solver_id == 0 ? 0 : 0 /* 1 */];
// can be disabled if use_push_bg == true
// solver::scoped_push _s_(*m_ctx);
if (!m_use_push_bg) { m_ctx->push(); }
itp_solver::scoped_bg _b_(*m_ctx);
if (!m_use_push_bg) {m_ctx->push();}
iuc_solver::scoped_bg _b_(*m_ctx);
for (unsigned i = 0; i < num_bg; ++i)
if (m_use_push_bg) { m_ctx->push_bg(bg [i]); }
@ -265,7 +376,9 @@ lbool prop_solver::check_assumptions(const expr_ref_vector & _hard,
unsigned soft_sz = soft.size();
(void) soft_sz;
lbool res = internal_check_assumptions(hard, soft);
vector<expr_ref_vector> clauses;
if (!clause.empty()) clauses.push_back(clause);
lbool res = internal_check_assumptions(hard, soft, clauses);
if (!m_use_push_bg) { m_ctx->pop(1); }
TRACE("psolve_verbose",

51
src/muz/spacer/spacer_prop_solver.h
View file

@ -29,25 +29,23 @@ Revision History:
#include "smt/smt_kernel.h"
#include "util/util.h"
#include "util/vector.h"
#include "muz/spacer/spacer_manager.h"
#include "muz/spacer/spacer_smt_context_manager.h"
#include "muz/spacer/spacer_itp_solver.h"
#include "solver/solver.h"
#include "muz/spacer/spacer_iuc_solver.h"
#include "muz/spacer/spacer_util.h"
struct fixedpoint_params;
struct fp_params;
namespace spacer {
typedef ptr_vector<func_decl> decl_vector;
class prop_solver {
private:
ast_manager& m;
manager& m_pm;
symbol m_name;
smt_params* m_fparams[2];
solver* m_solvers[2];
scoped_ptr<itp_solver> m_contexts[2];
itp_solver * m_ctx;
smt_params * m_ctx_fparams;
ref<solver> m_solvers[2];
scoped_ptr<iuc_solver> m_contexts[2];
iuc_solver * m_ctx;
decl_vector m_level_preds;
app_ref_vector m_pos_level_atoms; // atoms used to identify level
app_ref_vector m_neg_level_atoms; //
@ -68,13 +66,17 @@ private:
void ensure_level(unsigned lvl);
lbool internal_check_assumptions(expr_ref_vector &hard,
expr_ref_vector &soft);
expr_ref_vector &soft,
vector<expr_ref_vector> const & clause);
lbool maxsmt(expr_ref_vector &hard, expr_ref_vector &soft);
lbool maxsmt(expr_ref_vector &hard, expr_ref_vector &soft,
vector<expr_ref_vector> const & clauses);
lbool mss(expr_ref_vector &hard, expr_ref_vector &soft);
public:
prop_solver(spacer::manager& pm, fixedpoint_params const& p, symbol const& name);
prop_solver(ast_manager &m, solver *solver0, solver* solver1,
fp_params const& p, symbol const& name);
void set_core(expr_ref_vector* core) { m_core = core; }
@ -91,11 +93,19 @@ public:
void assert_expr(expr * form);
void assert_expr(expr * form, unsigned level);
void assert_exprs(const expr_ref_vector &fmls) {
for (auto *f : fmls) assert_expr(f);
}
void assert_exprs(const expr_ref_vector &fmls, unsigned level) {
for (auto *f : fmls) assert_expr(f, level);
}
/**
* check assumptions with a background formula
*/
lbool check_assumptions(const expr_ref_vector & hard,
expr_ref_vector & soft,
const expr_ref_vector &clause,
unsigned num_bg = 0,
expr * const *bg = nullptr,
unsigned solver_id = 0);
@ -136,7 +146,22 @@ public:
~scoped_delta_level() {m_delta = false;}
};
class scoped_weakness {
public:
solver *sol;
scoped_weakness(prop_solver &ps, unsigned solver_id, unsigned weakness)
: sol(nullptr) {
sol = ps.m_solvers[solver_id == 0 ? 0 : 0 /* 1 */].get();
if (!sol) return;
sol->push_params();
params_ref p;
p.set_bool("arith.ignore_int", weakness < 1);
p.set_bool("array.weak", weakness < 2);
sol->updt_params(p);
}
~scoped_weakness() {if (sol) {sol->pop_params();}}
};
};
}

10
src/muz/spacer/spacer_qe_project.cpp
View file

@ -41,7 +41,7 @@ Revision History:
#include "muz/spacer/spacer_mev_array.h"
#include "muz/spacer/spacer_qe_project.h"
namespace
namespace spacer_qe
{
bool is_partial_eq (app* a);
@ -186,7 +186,7 @@ bool is_partial_eq (app* a) {
}
namespace qe {
namespace spacer_qe {
class is_relevant_default : public i_expr_pred {
public:
@ -195,7 +195,7 @@ namespace qe {
}
};
class mk_atom_default : public i_nnf_atom {
class mk_atom_default : public qe::i_nnf_atom {
public:
void operator()(expr* e, bool pol, expr_ref& result) override {
if (pol) result = e;
@ -2254,7 +2254,7 @@ namespace qe {
void arith_project(model& mdl, app_ref_vector& vars, expr_ref& fml) {
ast_manager& m = vars.get_manager();
arith_project_util ap(m);
atom_set pos_lits, neg_lits;
qe::atom_set pos_lits, neg_lits;
is_relevant_default is_relevant;
mk_atom_default mk_atom;
get_nnf (fml, is_relevant, mk_atom, pos_lits, neg_lits);
@ -2264,7 +2264,7 @@ namespace qe {
void arith_project(model& mdl, app_ref_vector& vars, expr_ref& fml, expr_map& map) {
ast_manager& m = vars.get_manager();
arith_project_util ap(m);
atom_set pos_lits, neg_lits;
qe::atom_set pos_lits, neg_lits;
is_relevant_default is_relevant;
mk_atom_default mk_atom;
get_nnf (fml, is_relevant, mk_atom, pos_lits, neg_lits);

2
src/muz/spacer/spacer_qe_project.h
View file

@ -23,7 +23,7 @@ Notes:
#include "model/model.h"
#include "ast/expr_map.h"
namespace qe {
namespace spacer_qe {
/**
Loos-Weispfenning model-based projection for a basic conjunction.
Lits is a vector of literals.

671
src/muz/spacer/spacer_quant_generalizer.cpp Normal file
View file

@ -0,0 +1,671 @@
/*++
Copyright (c) 2017 Microsoft Corporation and Arie Gurfinkel
Module Name:
spacer_quant_generalizer.cpp
Abstract:
Quantified lemma generalizer.
Author:
Yakir Vizel
Arie Gurfinkel
Revision History:
--*/
#include "muz/spacer/spacer_context.h"
#include "muz/spacer/spacer_generalizers.h"
#include "muz/spacer/spacer_manager.h"
#include "ast/expr_abstract.h"
#include "ast/rewriter/var_subst.h"
#include "ast/for_each_expr.h"
#include "ast/factor_equivs.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/substitution/matcher.h"
#include "ast/expr_functors.h"
#include "muz/spacer/spacer_sem_matcher.h"
using namespace spacer;
namespace {
struct index_lt_proc : public std::binary_function<app*, app *, bool> {
arith_util m_arith;
index_lt_proc(ast_manager &m) : m_arith(m) {}
bool operator() (app *a, app *b) {
// XXX This order is a bit strange.
// XXX It does the job in our current application, but only because
// XXX we assume that we only compare expressions of the form (B + k),
// XXX where B is fixed and k is a number.
// XXX Might be better to specialize just for that specific use case.
rational val1, val2;
bool is_num1 = m_arith.is_numeral(a, val1);
bool is_num2 = m_arith.is_numeral(b, val2);
if (is_num1 && is_num2) {
return val1 < val2;
}
else if (is_num1 != is_num2) {
return is_num1;
}
is_num1 = false;
is_num2 = false;
// compare the first numeric argument of a to first numeric argument of b
// if available
for (unsigned i = 0, sz = a->get_num_args(); !is_num1 && i < sz; ++i) {
is_num1 = m_arith.is_numeral (a->get_arg(i), val1);
}
for (unsigned i = 0, sz = b->get_num_args(); !is_num2 && i < sz; ++i) {
is_num2 = m_arith.is_numeral(b->get_arg(i), val2);
}
if (is_num1 && is_num2) {
return val1 < val2;
}
else if (is_num1 != is_num2) {
return is_num1;
}
else {
return a->get_id() < b->get_id();
}
}
};
}
namespace spacer {
lemma_quantifier_generalizer::lemma_quantifier_generalizer(context &ctx,
bool normalize_cube) :
lemma_generalizer(ctx), m(ctx.get_ast_manager()), m_arith(m), m_cube(m),
m_normalize_cube(normalize_cube), m_offset(0) {}
void lemma_quantifier_generalizer::collect_statistics(statistics &st) const
{
st.update("time.spacer.solve.reach.gen.quant", m_st.watch.get_seconds());
st.update("quantifier gen", m_st.count);
st.update("quantifier gen failures", m_st.num_failures);
}
/**
Finds candidates terms to be existentially abstracted.
A term t is a candidate if
(a) t is ground
(b) t appears in an expression of the form (select A t) for some array A
(c) t appears in an expression of the form (select A (+ t v))
where v is ground
The goal is to pick candidates that might result in a lemma in the
essentially uninterpreted fragment of FOL or its extensions.
*/
void lemma_quantifier_generalizer::find_candidates(expr *e,
app_ref_vector &candidates) {
if (!contains_selects(e, m)) return;
app_ref_vector indices(m);
get_select_indices(e, indices, m);
app_ref_vector extra(m);
expr_sparse_mark marked_args;
// Make sure not to try and quantify already-quantified indices
for (unsigned idx=0, sz = indices.size(); idx < sz; idx++) {
// skip expressions that already contain a quantified variable
if (has_zk_const(indices.get(idx))) {
continue;
}
app *index = indices.get(idx);
TRACE ("spacer_qgen", tout << "Candidate: "<< mk_pp(index, m)
<< " in " << mk_pp(e, m) << "\n";);
extra.push_back(index);
if (m_arith.is_add(index)) {
for (expr * arg : *index) {
if (!is_app(arg) || marked_args.is_marked(arg)) {continue;}
marked_args.mark(arg);
candidates.push_back (to_app(arg));
}
}
}
std::sort(candidates.c_ptr(), candidates.c_ptr() + candidates.size(),
index_lt_proc(m));
// keep actual select indecies in the order found at the back of
// candidate list. There is no particular reason for this order
candidates.append(extra);
}
/// returns true if expression e contains a sub-expression of the form (select A idx) where
/// idx contains exactly one skolem from zks. Returns idx and the skolem
bool lemma_quantifier_generalizer::match_sk_idx(expr *e, app_ref_vector const &zks, expr *&idx, app *&sk) {
if (zks.size() != 1) return false;
contains_app has_zk(m, zks.get(0));
if (!contains_selects(e, m)) return false;
app_ref_vector indicies(m);
get_select_indices(e, indicies, m);
if (indicies.size() > 2) return false;
unsigned i=0;
if (indicies.size() == 1) {
if (!has_zk(indicies.get(0))) return false;
}
else {
if (has_zk(indicies.get(0)) && !has_zk(indicies.get(1)))
i = 0;
else if (!has_zk(indicies.get(0)) && has_zk(indicies.get(1)))
i = 1;
else if (!has_zk(indicies.get(0)) && !has_zk(indicies.get(1)))
return false;
}
idx = indicies.get(i);
sk = zks.get(0);
return true;
}
namespace {
expr* times_minus_one(expr *e, arith_util &arith) {
expr *r;
if (arith.is_times_minus_one (e, r)) { return r; }
return arith.mk_mul(arith.mk_numeral(rational(-1), arith.is_int(get_sort(e))), e);
}
}
/** Attempts to rewrite a cube so that quantified variable appears as
a top level argument of select-term
Find sub-expression of the form (select A (+ sk!0 t)) and replaces
(+ sk!0 t) --> sk!0 and sk!0 --> (+ sk!0 (* (- 1) t))
Current implementation is an ugly hack for one special case
*/
void lemma_quantifier_generalizer::cleanup(expr_ref_vector &cube, app_ref_vector const &zks, expr_ref &bind) {
if (zks.size() != 1) return;
arith_util arith(m);
expr *idx = nullptr;
app *sk = nullptr;
expr_ref rep(m);
for (expr *e : cube) {
if (match_sk_idx(e, zks, idx, sk)) {
CTRACE("spacer_qgen", idx != sk,
tout << "Possible cleanup of " << mk_pp(idx, m) << " in "
<< mk_pp(e, m) << " on " << mk_pp(sk, m) << "\n";);
if (!arith.is_add(idx)) continue;
app *a = to_app(idx);
bool found = false;
expr_ref_vector kids(m);
expr_ref_vector kids_bind(m);
for (expr* arg : *a) {
if (arg == sk) {
found = true;
kids.push_back(arg);
kids_bind.push_back(bind);
}
else {
kids.push_back (times_minus_one(arg, arith));
kids_bind.push_back (times_minus_one(arg, arith));
}
}
if (!found) continue;
rep = arith.mk_add(kids.size(), kids.c_ptr());
bind = arith.mk_add(kids_bind.size(), kids_bind.c_ptr());
TRACE("spacer_qgen",
tout << "replace " << mk_pp(idx, m) << " with " << mk_pp(rep, m) << "\n";);
break;
}
}
if (rep) {
expr_safe_replace rw(m);
rw.insert(sk, rep);
rw.insert(idx, sk);
rw(cube);
TRACE("spacer_qgen",
tout << "Cleaned cube to: " << mk_and(cube) << "\n";);
}
}
/**
Create an abstract cube by abstracting a given term with a given variable.
On return,
gnd_cube contains all ground literals from m_cube
abs_cube contains all newly quantified literals from m_cube
lb contains an expression determining the lower bound on the variable
ub contains an expression determining the upper bound on the variable
Conjunction of gnd_cube and abs_cube is the new quantified cube
lb and ub are null if no bound was found
*/
void lemma_quantifier_generalizer::mk_abs_cube(lemma_ref &lemma, app *term, var *var,
expr_ref_vector &gnd_cube,
expr_ref_vector &abs_cube,
expr *&lb, expr *&ub, unsigned &stride) {
// create an abstraction function that maps candidate term to variables
expr_safe_replace sub(m);
// term -> var
sub.insert(term , var);
rational val;
if (m_arith.is_numeral(term, val)) {
bool is_int = val.is_int();
expr_ref minus_one(m);
minus_one = m_arith.mk_numeral(rational(-1), is_int);
// term+1 -> var+1 if term is a number
sub.insert(
m_arith.mk_numeral(val + 1, is_int),
m_arith.mk_add(var, m_arith.mk_numeral(rational(1), is_int)));
// -term-1 -> -1*var + -1 if term is a number
sub.insert(
m_arith.mk_numeral(-1*val + -1, is_int),
m_arith.mk_add (m_arith.mk_mul (minus_one, var), minus_one));
}
lb = nullptr;
ub = nullptr;
for (expr *lit : m_cube) {
expr_ref abs_lit(m);
sub (lit, abs_lit);
if (lit == abs_lit) {
gnd_cube.push_back(lit);
}
else {
expr *e1, *e2;
// generalize v=num into v>=num
if (m.is_eq(abs_lit, e1, e2) && (e1 == var || e2 == var)) {
if (m_arith.is_numeral(e1)) {
abs_lit = m_arith.mk_ge (var, e1);
} else if (m_arith.is_numeral(e2)) {
abs_lit = m_arith.mk_ge(var, e2);
}
}
abs_cube.push_back(abs_lit);
if (contains_selects(abs_lit, m)) {
expr_ref_vector pob_cube(m);
flatten_and(lemma->get_pob()->post(), pob_cube);
find_stride(pob_cube, abs_lit, stride);
}
if (!lb && is_lb(var, abs_lit)) {
lb = abs_lit;
}
else if (!ub && is_ub(var, abs_lit)) {
ub = abs_lit;
}
}
}
}
// -- returns true if e is an upper bound for var
bool lemma_quantifier_generalizer::is_ub(var *var, expr *e) {
expr *e1, *e2;
// var <= e2
if ((m_arith.is_le (e, e1, e2) || m_arith.is_lt(e, e1, e2)) && var == e1) {
return true;
}
// e1 >= var
if ((m_arith.is_ge(e, e1, e2) || m_arith.is_gt(e, e1, e2)) && var == e2) {
return true;
}
// t <= -1*var
if ((m_arith.is_le (e, e1, e2) || m_arith.is_lt(e, e1, e2))
&& m_arith.is_times_minus_one(e2, e2) && e2 == var) {
return true;
}
// -1*var >= t
if ((m_arith.is_ge(e, e1, e2) || m_arith.is_gt(e, e1, e2)) &&
m_arith.is_times_minus_one(e1, e1) && e1 == var) {
return true;
}
// ! (var >= e2)
if (m.is_not (e, e1) && is_lb(var, e1)) {
return true;
}
// var + t1 <= t2
if ((m_arith.is_le(e, e1, e2) || m_arith.is_lt(e, e1, e2)) &&
m_arith.is_add(e1)) {
app *a = to_app(e1);
for (expr* arg : *a) {
if (arg == var) return true;
}
}
// t1 <= t2 + -1*var
if ((m_arith.is_le(e, e1, e2) || m_arith.is_lt(e, e1, e2)) &&
m_arith.is_add(e2)) {
app *a = to_app(e2);
for (expr* arg : *a) {
if (m_arith.is_times_minus_one(arg, arg) && arg == var)
return true;
}
}
// t1 >= t2 + var
if ((m_arith.is_ge(e, e1, e2) || m_arith.is_gt(e, e1, e2)) &&
m_arith.is_add(e2)) {
app *a = to_app(e2);
for (expr * arg : *a) {
if (arg == var) return true;
}
}
// -1*var + t1 >= t2
if ((m_arith.is_ge(e, e1, e2) || m_arith.is_gt(e, e1, e2)) &&
m_arith.is_add(e1)) {
app *a = to_app(e1);
for (expr * arg : *a) {
if (m_arith.is_times_minus_one(arg, arg) && arg == var)
return true;
}
}
return false;
}
// -- returns true if e is a lower bound for var
bool lemma_quantifier_generalizer::is_lb(var *var, expr *e) {
expr *e1, *e2;
// var >= e2
if ((m_arith.is_ge (e, e1, e2) || m_arith.is_gt(e, e1, e2)) && var == e1) {
return true;
}
// e1 <= var
if ((m_arith.is_le(e, e1, e2) || m_arith.is_lt(e, e1, e2)) && var == e2) {
return true;
}
// t >= -1*var
if ((m_arith.is_ge (e, e1, e2) || m_arith.is_gt(e, e1, e2))
&& m_arith.is_times_minus_one(e2, e2) && e2 == var) {
return true;
}
// -1*var <= t
if ((m_arith.is_le(e, e1, e2) || m_arith.is_lt(e, e1, e2)) &&
m_arith.is_times_minus_one(e1, e1) && e1 == var) {
return true;
}
// ! (var <= e2)
if (m.is_not (e, e1) && is_ub(var, e1)) {
return true;
}
// var + t1 >= t2
if ((m_arith.is_ge(e, e1, e2) || m_arith.is_gt(e, e1, e2)) &&
m_arith.is_add(e1)) {
app *a = to_app(e1);
for (expr * arg : *a) {
if (arg == var) return true;
}
}
// t1 >= t2 + -1*var
if ((m_arith.is_ge(e, e1, e2) || m_arith.is_gt(e, e1, e2)) &&
m_arith.is_add(e2)) {
app *a = to_app(e2);
for (expr * arg : *a) {
if (m_arith.is_times_minus_one(arg, arg) && arg == var)
return true;
}
}
// t1 <= t2 + var
if ((m_arith.is_le(e, e1, e2) || m_arith.is_lt(e, e1, e2)) &&
m_arith.is_add(e2)) {
app *a = to_app(e2);
for (expr * arg : *a) {
if (arg == var) return true;
}
}
// -1*var + t1 <= t2
if ((m_arith.is_le(e, e1, e2) || m_arith.is_lt(e, e1, e2)) &&
m_arith.is_add(e1)) {
app *a = to_app(e1);
for (expr * arg : *a) {
if (m_arith.is_times_minus_one(arg, arg) && arg == var)
return true;
}
}
return false;
}
bool lemma_quantifier_generalizer::generalize (lemma_ref &lemma, app *term) {
expr *lb = nullptr, *ub = nullptr;
unsigned stride = 1;
expr_ref_vector gnd_cube(m);
expr_ref_vector abs_cube(m);
var_ref var(m);
var = m.mk_var (m_offset, get_sort(term));
mk_abs_cube(lemma, term, var, gnd_cube, abs_cube, lb, ub, stride);
if (abs_cube.empty()) {return false;}
TRACE("spacer_qgen",
tout << "abs_cube is: " << mk_and(abs_cube) << "\n";
tout << "lb = ";
if (lb) tout << mk_pp(lb, m); else tout << "none";
tout << "\n";
tout << "ub = ";
if (ub) tout << mk_pp(ub, m); else tout << "none";
tout << "\n";);
if (!lb && !ub)
return false;
// -- guess lower or upper bound if missing
if (!lb) {
abs_cube.push_back (m_arith.mk_ge (var, term));
lb = abs_cube.back();
}
if (!ub) {
abs_cube.push_back (m_arith.mk_lt(var, term));
ub = abs_cube.back();
}
rational init;
expr_ref constant(m);
if (is_var(to_app(lb)->get_arg(0)))
constant = to_app(lb)->get_arg(1);
else
constant = to_app(lb)->get_arg(0);
if (stride > 1 && m_arith.is_numeral(constant, init)) {
unsigned mod = init.get_unsigned() % stride;
TRACE("spacer_qgen",
tout << "mod=" << mod << " init=" << init << " stride=" << stride << "\n";
tout.flush(););
abs_cube.push_back(m.mk_eq(
m_arith.mk_mod(var, m_arith.mk_numeral(rational(stride), true)),
m_arith.mk_numeral(rational(mod), true)));
}
// skolemize
expr_ref gnd(m);
app_ref_vector zks(m);
ground_expr(mk_and(abs_cube), gnd, zks);
flatten_and(gnd, gnd_cube);
TRACE("spacer_qgen",
tout << "New CUBE is: " << gnd_cube << "\n";);
// check if the result is a true lemma
unsigned uses_level = 0;
pred_transformer &pt = lemma->get_pob()->pt();
if (pt.check_inductive(lemma->level(), gnd_cube, uses_level, lemma->weakness())) {
TRACE("spacer_qgen",
tout << "Quantifier Generalization Succeeded!\n"
<< "New CUBE is: " << gnd_cube << "\n";);
SASSERT(zks.size() >= static_cast<unsigned>(m_offset));
// lift quantified variables to top of select
expr_ref ext_bind(m);
ext_bind = term;
cleanup(gnd_cube, zks, ext_bind);
// XXX better do that check before changing bind in cleanup()
// XXX Or not because substitution might introduce _n variable into bind
if (m_ctx.get_manager().is_n_formula(ext_bind)) {
// XXX this creates an instance, but not necessarily the needed one
// XXX This is sound because any instance of
// XXX universal quantifier is sound
// XXX needs better long term solution. leave
// comment here for the future
m_ctx.get_manager().formula_n2o(ext_bind, ext_bind, 0);
}
lemma->update_cube(lemma->get_pob(), gnd_cube);
lemma->set_level(uses_level);
SASSERT(var->get_idx() < zks.size());
SASSERT(is_app(ext_bind));
lemma->add_skolem(zks.get(var->get_idx()), to_app(ext_bind));
return true;
}
return false;
}
bool lemma_quantifier_generalizer::find_stride(expr_ref_vector &c, expr_ref &pattern, unsigned &stride) {
expr_ref tmp(m);
tmp = mk_and(c);
normalize(tmp, tmp, false, true);
c.reset();
flatten_and(tmp, c);
app_ref_vector indices(m);
get_select_indices(pattern, indices, m);
// TODO
if (indices.size() > 1)
return false;
app *p_index = indices.get(0);
if (is_var(p_index)) return false;
std::vector<unsigned> instances;
for (expr* lit : c) {
if (!contains_selects(lit, m))
continue;
indices.reset();
get_select_indices(lit, indices, m);
// TODO:
if (indices.size() > 1)
continue;
app *candidate = indices.get(0);
unsigned size = p_index->get_num_args();
unsigned matched = 0;
for (unsigned p=0; p < size; p++) {
expr *arg = p_index->get_arg(p);
if (is_var(arg)) {
rational val;
if (p < candidate->get_num_args() &&
m_arith.is_numeral(candidate->get_arg(p), val) &&
val.is_unsigned()) {
instances.push_back(val.get_unsigned());
}
}
else {
for (expr* cand : *candidate) {
if (cand == arg) {
matched++;
break;
}
}
}
}
if (matched < size - 1)
continue;
if (candidate->get_num_args() == matched)
instances.push_back(0);
TRACE("spacer_qgen",
tout << "Match succeeded!\n";);
}
if (instances.size() <= 1)
return false;
std::sort(instances.begin(), instances.end());
stride = instances[1]-instances[0];
TRACE("spacer_qgen", tout << "Index Stride is: " << stride << "\n";);
return true;
}
void lemma_quantifier_generalizer::operator()(lemma_ref &lemma) {
if (lemma->get_cube().empty()) return;
if (!lemma->has_pob()) return;
m_st.count++;
scoped_watch _w_(m_st.watch);
TRACE("spacer_qgen",
tout << "initial cube: " << mk_and(lemma->get_cube()) << "\n";);
// setup the cube
m_cube.reset();
m_cube.append(lemma->get_cube());
if (m_normalize_cube) {
// -- re-normalize the cube
expr_ref c(m);
c = mk_and(m_cube);
normalize(c, c, false, true);
m_cube.reset();
flatten_and(c, m_cube);
TRACE("spacer_qgen",
tout << "normalized cube:\n" << mk_and(m_cube) << "\n";);
}
// first unused free variable
m_offset = lemma->get_pob()->get_free_vars_size();
// for every literal, find a candidate term to abstract
for (unsigned i=0; i < m_cube.size(); i++) {
expr *r = m_cube.get(i);
// generate candidates for abstraction
app_ref_vector candidates(m);
find_candidates(r, candidates);
if (candidates.empty()) continue;
// for every candidate
for (unsigned arg=0, sz = candidates.size(); arg < sz; arg++) {
if (generalize (lemma, candidates.get(arg))) {
return;
}
else {
++m_st.num_failures;
}
}
}
}
}

178
src/muz/spacer/spacer_sat_answer.cpp Normal file
View file

@ -0,0 +1,178 @@
#include "muz/spacer/spacer_sat_answer.h"
#include "muz/base/dl_context.h"
#include "muz/base/dl_rule.h"
#include "smt/smt_solver.h"
namespace spacer {
struct ground_sat_answer_op::frame {
reach_fact *m_rf;
pred_transformer &m_pt;
expr_ref_vector m_gnd_subst;
expr_ref m_gnd_eq;
expr_ref m_fact;
unsigned m_visit;
expr_ref_vector m_kids;
frame(reach_fact *rf, pred_transformer &pt, const expr_ref_vector &gnd_subst) :
m_rf(rf), m_pt(pt),
m_gnd_subst(gnd_subst),
m_gnd_eq(pt.get_ast_manager()),
m_fact(pt.get_ast_manager()),
m_visit(0),
m_kids(pt.get_ast_manager()) {
ast_manager &m = pt.get_ast_manager();
spacer::manager &pm = pt.get_manager();
m_fact = m.mk_app(head(), m_gnd_subst.size(), m_gnd_subst.c_ptr());
if (pt.head()->get_arity() == 0)
m_gnd_eq = m.mk_true();
else {
SASSERT(m_gnd_subst.size() == pt.head()->get_arity());
for (unsigned i = 0, sz = pt.sig_size(); i < sz; ++i) {
m_gnd_eq = m.mk_eq(m.mk_const(pm.o2n(pt.sig(i), 0)),
m_gnd_subst.get(i));
}
}
}
func_decl* head() {return m_pt.head();}
expr* fact() {return m_fact;}
const datalog::rule &rule() {return m_rf->get_rule();}
pred_transformer &pt() {return m_pt;}
};
ground_sat_answer_op::ground_sat_answer_op(context &ctx) :
m_ctx(ctx), m(m_ctx.get_ast_manager()), m_pm(m_ctx.get_manager()),
m_pinned(m) {
m_solver = mk_smt_solver(m, params_ref::get_empty(), symbol::null);
}
proof_ref ground_sat_answer_op::operator()(pred_transformer &query) {
vector<frame> todo, new_todo;
// -- find substitution for a query if query is not nullary
expr_ref_vector qsubst(m);
if (query.head()->get_arity() > 0) {
solver::scoped_push _s_(*m_solver);
m_solver->assert_expr(query.get_last_rf()->get());
lbool res = m_solver->check_sat(0, nullptr);
(void)res;
SASSERT(res == l_true);
model_ref mdl;
m_solver->get_model(mdl);
for (unsigned i = 0, sz = query.sig_size(); i < sz; ++i) {
expr_ref arg(m), val(m);
arg = m.mk_const(m_pm.o2n(query.sig(i), 0));
mdl->eval(arg, val, true);
qsubst.push_back(val);
}
}
todo.push_back(frame(query.get_last_rf(), query, qsubst));
expr_ref root_fact(m);
root_fact = todo.back().fact();
while (!todo.empty()) {
frame &curr = todo.back();
if (m_cache.contains(curr.fact())) {
todo.pop_back();
continue;
}
if (curr.m_visit == 0) {
new_todo.reset();
mk_children(curr, new_todo);
curr.m_visit = 1;
// curr becomes invalid
todo.append(new_todo);
}
else {
proof* pf = mk_proof_step(curr);
m_pinned.push_back(curr.fact());
m_cache.insert(curr.fact(), pf);
todo.pop_back();
}
}
return proof_ref(m_cache.find(root_fact), m);
}
void ground_sat_answer_op::mk_children(frame &fr, vector<frame> &todo) {
const datalog::rule &r = fr.rule();
ptr_vector<func_decl> preds;
fr.pt().find_predecessors(r, preds);
if (preds.empty()) return;
const reach_fact_ref_vector &kid_rfs = fr.m_rf->get_justifications();
solver::scoped_push _s_(*m_solver);
m_solver->assert_expr(fr.m_gnd_eq);
unsigned ut_sz = r.get_uninterpreted_tail_size();
for (unsigned i = 0; i < ut_sz; ++i) {
expr_ref f(m);
m_pm.formula_n2o(kid_rfs.get(i)->get(), f, i);
m_solver->assert_expr(f);
}
m_solver->assert_expr(fr.pt().transition());
m_solver->assert_expr(fr.pt().rule2tag(&r));
lbool res = m_solver->check_sat(0, nullptr);
(void)res;
VERIFY(res == l_true);
model_ref mdl;
m_solver->get_model(mdl);
expr_ref_vector subst(m);
for (unsigned i = 0, sz = preds.size(); i < sz; ++i) {
subst.reset();
mk_child_subst_from_model(preds.get(i), i, mdl, subst);
todo.push_back(frame(kid_rfs.get(i),
m_ctx.get_pred_transformer(preds.get(i)), subst));
fr.m_kids.push_back(todo.back().fact());
}
}
void ground_sat_answer_op::mk_child_subst_from_model(func_decl *pred,
unsigned j, model_ref &mdl,
expr_ref_vector &subst) {
pred_transformer &pt = m_ctx.get_pred_transformer(pred);
for (unsigned i = 0, sz = pt.sig_size(); i < sz; ++i) {
expr_ref arg(m), val(m);
arg = m.mk_const(m_pm.o2o(pt.sig(i), 0, j));
mdl->eval(arg, val, true);
subst.push_back(val);
}
}
proof *ground_sat_answer_op::mk_proof_step(frame &fr) {
svector<std::pair<unsigned, unsigned>> positions;
vector<expr_ref_vector> substs;
proof_ref_vector premises(m);
datalog::rule_manager &rm = m_ctx.get_datalog_context().get_rule_manager();
expr_ref rule_fml(m);
rm.to_formula(fr.rule(), rule_fml);
// premises.push_back(fr.rule().get_proof());
premises.push_back(m.mk_asserted(rule_fml));
for (auto &k : fr.m_kids) {premises.push_back(m_cache.find(k));}
for (unsigned i = 0; i < premises.size(); i++) {
positions.push_back(std::make_pair(0,i));
}
for (unsigned i = 0; i <= premises.size(); i++) {
substs.push_back(expr_ref_vector(m));
}
m_pinned.push_back(m.mk_hyper_resolve(premises.size(),
premises.c_ptr(),
fr.fact(),
positions, substs));
return to_app(m_pinned.back());
}
}

55
src/muz/spacer/spacer_sat_answer.h Normal file
View file

@ -0,0 +1,55 @@
/*++
Copyright (c) 2018 Arie Gurfinkel
Module Name:
spacer_sat_answer.h
Abstract:
Compute refutation proof for CHC
Author:
Arie Gurfinkel
Revision History:
--*/
#ifndef _SPACER_SAT_ANSWER_H_
#define _SPACER_SAT_ANSWER_H_
#include "muz/spacer/spacer_context.h"
#include "ast/ast.h"
#include "util/obj_hashtable.h"
#include "model/model.h"
#include "solver/solver.h"
namespace spacer {
class ground_sat_answer_op {
context &m_ctx;
ast_manager &m;
manager &m_pm;
expr_ref_vector m_pinned;
obj_map<expr, proof*> m_cache;
ref<solver> m_solver;
struct frame;
proof *mk_proof_step(frame &fr);
void mk_children(frame &fr, vector<frame> &todo);
void mk_child_subst_from_model(func_decl *pred, unsigned i,
model_ref &mdl, expr_ref_vector &subst);
public:
ground_sat_answer_op(context &ctx);
proof_ref operator() (pred_transformer &query);
};
}
#endif

147
src/muz/spacer/spacer_sem_matcher.cpp Normal file
View file

@ -0,0 +1,147 @@
/*++
Copyright (c) 2006 Microsoft Corporation and Arie Gurfinkel
Module Name:
sem_matcher.cpp
Abstract:
<abstract>
Author:
Leonardo de Moura (leonardo) 2008-02-02.
Arie Gurfinkel
Revision History:
--*/
#include "muz/spacer/spacer_sem_matcher.h"
namespace spacer {
sem_matcher::sem_matcher(ast_manager &man) : m(man), m_arith(m), m_pinned(m) {}
bool sem_matcher::match_var (var *v, expr *e) {
expr_offset r;
if (m_subst->find(v, 0, r)) {
if (!m.are_equal(r.get_expr(), e)) {
return false;
}
}
else {
m_subst->insert(v, 0, expr_offset(e, 1));
}
return true;
}
bool sem_matcher::operator()(expr * e1, expr * e2, substitution & s, bool &pos) {
reset();
m_subst = &s;
m_todo.push_back(expr_pair(e1, e2));
// true on the first run through the loop
bool top = true;
pos = true;
while (!m_todo.empty()) {
expr_pair const & p = m_todo.back();
if (is_var(p.first)) {
if (!match_var(to_var(p.first), p.second)) {
return false;
}
m_todo.pop_back();
top = false;
continue;
}
if (is_var(p.second))
return false;
if (!is_app(p.first))
return false;
if (!is_app(p.second))
return false;
app * n1 = to_app(p.first);
app * n2 = to_app(p.second);
expr *t = nullptr;
// strip negation
if (top && n1->get_decl() != n2->get_decl()) {
if (m.is_not(n1, t) && !m.is_not(n2) && is_app(t) &&
to_app(t)->get_decl() == n2->get_decl()) {
pos = false;
n1 = to_app(e1);
}
else if (!m.is_not(n1) && m.is_not(n2, t) && is_app(t) &&
to_app(t)->get_decl() == n1->get_decl()) {
pos = false;
n2 = to_app(t);
}
}
top = false;
if (n1->get_decl() != n2->get_decl()) {
expr *e1 = nullptr, *e2 = nullptr;
rational val1, val2;
// x<=y == !(x>y)
if (m_arith.is_le(n1) && m.is_not(n2, t) && m_arith.is_gt(t)) {
n2 = to_app(t);
}
else if (m_arith.is_le(n2) && m.is_not(n1, t) && m_arith.is_gt(t)) {
n1 = to_app(t);
}
// x>=y == !(x<y)
if (m_arith.is_ge(n1) && m.is_not(n2, t) && m_arith.is_lt(t)) {
n2 = to_app(t);
}
else if (m_arith.is_ge(n2) && m.is_not(n1, t) && m_arith.is_lt(t)) {
n1 = to_app(t);
}
// x+val1 matched to val2, where x is a variable, and
// val1, val2 are numerals
if (m_arith.is_numeral(n2, val2) && m_arith.is_add(n1, e1, e2) &&
m_arith.is_numeral(e2, val1) && is_var(e1)) {
val1 = val2 - val1;
expr_ref num1(m);
num1 = m_arith.mk_numeral (val1, val1.is_int());
m_pinned.push_back(num1);
if (!match_var (to_var(e1), num1)) {
return false;
}
m_todo.pop_back();
continue;
}
else {
return false;
}
}
unsigned num_args1 = n1->get_num_args();
if (num_args1 != n2->get_num_args())
return false;
m_todo.pop_back();
if (num_args1 == 0)
continue;
unsigned j = num_args1;
while (j > 0) {
--j;
m_todo.push_back(expr_pair(n1->get_arg(j), n2->get_arg(j)));
}
}
return true;
}
void sem_matcher::reset() {
m_todo.reset();
m_pinned.reset();
}
}

69
src/muz/spacer/spacer_sem_matcher.h Normal file
View file

@ -0,0 +1,69 @@
/*++
Copyright (c) 2006 Microsoft Corporation and Arie Gurfinkel
Module Name:
sem_matcher.h
Abstract:
Semantic matcher
Author:
Leonardo de Moura (leonardo) 2008-02-02.
Arie Gurfinkel
Revision History:
--*/
#ifndef SPACER_SEM_MATCHER_H_
#define SPACER_SEM_MATCHER_H_
#include "ast/substitution/substitution.h"
#include "ast/arith_decl_plugin.h"
#include "util/hashtable.h"
namespace spacer {
/**
\brief Functor for matching expressions.
*/
class sem_matcher {
typedef std::pair<expr *, expr *> expr_pair;
typedef pair_hash<obj_ptr_hash<expr>, obj_ptr_hash<expr> > expr_pair_hash;
typedef hashtable<expr_pair, expr_pair_hash, default_eq<expr_pair> > cache;
ast_manager &m;
arith_util m_arith;
expr_ref_vector m_pinned;
substitution * m_subst;
svector<expr_pair> m_todo;
void reset();
bool match_var(var *v, expr *e);
public:
sem_matcher(ast_manager &man);
/**
\brief Return true if e2 is an instance of e1.
In case of success (result is true), it will store the substitution that makes e1 equals to e2 into s.
Sets pos to true if the match is positive and to false if it is negative (i.e., e1 equals !e2)
For example:
1) e1 = f(g(x), x), e2 = f(g(h(a)), h(a))
The result is true, and s will contain x -> h(a)
2) e1 = f(a, x) e2 = f(x, a)
The result is false.
3) e1 = f(x, x) e2 = f(y, a)
The result is false
4) e1 = f(x, y) e2 = f(h(z), a)
The result is true, and s contains x->h(z) and y->a
*/
bool operator()(expr * e1, expr * e2, substitution & s, bool &pos);
};
}
#endif /* SPACER_SEM_MATCHER_H_ */

79
src/muz/spacer/spacer_smt_context_manager.cpp
View file

@ -1,79 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
spacer_smt_context_manager.cpp
Abstract:
Manager of smt contexts
Author:
Nikolaj Bjorner (nbjorner) 2011-11-26.
Arie Gurfinkel
Revision History:
--*/
#include "ast/ast_pp.h"
#include "ast/ast_pp_util.h"
#include "ast/ast_smt_pp.h"
#include "smt/smt_context.h"
#include "smt/params/smt_params.h"
#include "muz/spacer/spacer_util.h"
#include "muz/spacer/spacer_smt_context_manager.h"
namespace spacer {
smt_context_manager::smt_context_manager(ast_manager &m,
unsigned max_num_contexts,
const params_ref &p) :
m_fparams(p),
m(m),
m_max_num_contexts(max_num_contexts),
m_num_contexts(0) { m_stats.reset();}
smt_context_manager::~smt_context_manager()
{
std::for_each(m_solvers.begin(), m_solvers.end(),
delete_proc<spacer::virtual_solver_factory>());
}
virtual_solver* smt_context_manager::mk_fresh()
{
++m_num_contexts;
virtual_solver_factory *solver_factory = nullptr;
if (m_max_num_contexts == 0 || m_solvers.size() < m_max_num_contexts) {
m_solvers.push_back(alloc(spacer::virtual_solver_factory, m, m_fparams));
solver_factory = m_solvers.back();
} else
{ solver_factory = m_solvers[(m_num_contexts - 1) % m_max_num_contexts]; }
return solver_factory->mk_solver();
}
void smt_context_manager::collect_statistics(statistics& st) const
{
for (unsigned i = 0; i < m_solvers.size(); ++i) {
m_solvers[i]->collect_statistics(st);
}
}
void smt_context_manager::reset_statistics()
{
for (unsigned i = 0; i < m_solvers.size(); ++i) {
m_solvers[i]->reset_statistics();
}
}
};

68
src/muz/spacer/spacer_smt_context_manager.h
View file

@ -1,68 +0,0 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Module Name:
spacer_smt_context_manager.h
Abstract:
Manager of smt contexts
Author:
Nikolaj Bjorner (nbjorner) 2011-11-26.
Arie Gurfinkel
Revision History:
--*/
#ifndef _SPACER_SMT_CONTEXT_MANAGER_H_
#define _SPACER_SMT_CONTEXT_MANAGER_H_
#include "util/stopwatch.h"
#include "smt/smt_kernel.h"
#include "muz/base/dl_util.h"
#include "muz/spacer/spacer_virtual_solver.h"
namespace spacer {
class smt_context_manager {
struct stats {
unsigned m_num_smt_checks;
unsigned m_num_sat_smt_checks;
stats() { reset(); }
void reset() { memset(this, 0, sizeof(*this)); }
};
smt_params m_fparams;
ast_manager& m;
unsigned m_max_num_contexts;
ptr_vector<virtual_solver_factory> m_solvers;
unsigned m_num_contexts;
stats m_stats;
stopwatch m_check_watch;
stopwatch m_check_sat_watch;
public:
smt_context_manager(ast_manager& m, unsigned max_num_contexts = 1,
const params_ref &p = params_ref::get_empty());
~smt_context_manager();
virtual_solver* mk_fresh();
void collect_statistics(statistics& st) const;
void reset_statistics();
void updt_params(params_ref const &p) { m_fparams.updt_params(p); }
smt_params& fparams() {return m_fparams;}
};
};
#endif

596
src/muz/spacer/spacer_sym_mux.cpp
View file

@ -1,5 +1,5 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Copyright (c) 2018 Arie Gurfinkel and Microsoft Corporation
Module Name:
@ -7,10 +7,12 @@ Module Name:
Abstract:
A symbol multiplexer that helps with having multiple versions of each of a set of symbols.
A symbol multiplexer that helps with having multiple versions of
each of a set of symbols.
Author:
Arie Gurfinkel
Krystof Hoder (t-khoder) 2011-9-8.
Revision History:
@ -22,345 +24,123 @@ Revision History:
#include "ast/rewriter/rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "model/model.h"
#include "muz/spacer/spacer_util.h"
#include "muz/spacer/spacer_sym_mux.h"
using namespace spacer;
sym_mux::sym_mux(ast_manager & m, const std::vector<std::string> & suffixes)
: m(m), m_ref_holder(m), m_next_sym_suffix_idx(0), m_suffixes(suffixes)
{
for (std::string const& s : m_suffixes) {
m_used_suffixes.insert(symbol(s.c_str()));
sym_mux::sym_mux(ast_manager & m) : m(m) {}
sym_mux::~sym_mux() {
for (auto &entry : m_entries) {
dealloc(entry.m_value);
}
}
std::string sym_mux::get_suffix(unsigned i) const
{
while (m_suffixes.size() <= i) {
std::string new_suffix;
symbol new_syffix_sym;
do {
std::stringstream stm;
stm << '_' << m_next_sym_suffix_idx;
m_next_sym_suffix_idx++;
new_suffix = stm.str();
new_syffix_sym = symbol(new_suffix.c_str());
} while (m_used_suffixes.contains(new_syffix_sym));
m_used_suffixes.insert(new_syffix_sym);
m_suffixes.push_back(new_suffix);
}
return m_suffixes[i];
func_decl_ref sym_mux::mk_variant(func_decl *fdecl, unsigned i) const {
func_decl_ref v(m);
std::string name = fdecl->get_name().str();
std::string suffix = "_";
suffix += i == 0 ? "n" : std::to_string(i - 1);
name += suffix;
v = m.mk_func_decl(symbol(name.c_str()), fdecl->get_arity(),
fdecl->get_domain(), fdecl->get_range());
return v;
}
void sym_mux::create_tuple(func_decl* prefix, unsigned arity, sort * const * domain, sort * range,
unsigned tuple_length, decl_vector & tuple)
{
SASSERT(tuple_length > 0);
while (tuple.size() < tuple_length) {
tuple.push_back(0);
}
SASSERT(tuple.size() == tuple_length);
std::string pre = prefix->get_name().str();
for (unsigned i = 0; i < tuple_length; i++) {
void sym_mux::register_decl(func_decl *fdecl) {
sym_mux_entry *entry = alloc(sym_mux_entry, m);
entry->m_main = fdecl;
entry->m_variants.push_back(mk_variant(fdecl, 0));
entry->m_variants.push_back(mk_variant(fdecl, 1));
if (tuple[i] != 0) {
SASSERT(tuple[i]->get_arity() == arity);
SASSERT(tuple[i]->get_range() == range);
//domain should match as well, but we won't bother checking an array equality
} else {
std::string name = pre + get_suffix(i);
tuple[i] = m.mk_func_decl(symbol(name.c_str()), arity, domain, range);
}
m_ref_holder.push_back(tuple[i]);
m_sym2idx.insert(tuple[i], i);
m_sym2prim.insert(tuple[i], tuple[0]);
}
m_prim2all.insert(tuple[0], tuple);
m_prefix2prim.insert(prefix, tuple[0]);
m_prim2prefix.insert(tuple[0], prefix);
m_prim_preds.push_back(tuple[0]);
m_ref_holder.push_back(prefix);
m_entries.insert(fdecl, entry);
m_muxes.insert(entry->m_variants.get(0), std::make_pair(entry, 0));
m_muxes.insert(entry->m_variants.get(1), std::make_pair(entry, 1));
}
void sym_mux::ensure_tuple_size(func_decl * prim, unsigned sz) const
{
SASSERT(m_prim2all.contains(prim));
decl_vector& tuple = m_prim2all.find_core(prim)->get_data().m_value;
SASSERT(tuple[0] == prim);
if (sz <= tuple.size()) { return; }
func_decl * prefix;
TRUSTME(m_prim2prefix.find(prim, prefix));
std::string prefix_name = prefix->get_name().bare_str();
for (unsigned i = tuple.size(); i < sz; ++i) {
std::string name = prefix_name + get_suffix(i);
func_decl * new_sym = m.mk_func_decl(symbol(name.c_str()), prefix->get_arity(),
prefix->get_domain(), prefix->get_range());
tuple.push_back(new_sym);
m_ref_holder.push_back(new_sym);
m_sym2idx.insert(new_sym, i);
m_sym2prim.insert(new_sym, prim);
void sym_mux::ensure_capacity(sym_mux_entry &entry, unsigned sz) const {
while (entry.m_variants.size() < sz) {
unsigned idx = entry.m_variants.size();
entry.m_variants.push_back (mk_variant(entry.m_main, idx));
m_muxes.insert(entry.m_variants.back(), std::make_pair(&entry, idx));
}
}
func_decl * sym_mux::conv(func_decl * sym, unsigned src_idx, unsigned tgt_idx) const
{
if (src_idx == tgt_idx) { return sym; }
func_decl * prim = (src_idx == 0) ? sym : get_primary(sym);
if (tgt_idx > src_idx) {
ensure_tuple_size(prim, tgt_idx + 1);
}
decl_vector & sym_vect = m_prim2all.find_core(prim)->get_data().m_value;
SASSERT(sym_vect[src_idx] == sym);
return sym_vect[tgt_idx];
bool sym_mux::find_idx(func_decl * sym, unsigned & idx) const {
std::pair<sym_mux_entry *, unsigned> entry;
if (m_muxes.find(sym, entry)) {idx = entry.second; return true;}
return false;
}
func_decl * sym_mux::get_or_create_symbol_by_prefix(func_decl* prefix, unsigned idx,
unsigned arity, sort * const * domain, sort * range)
{
func_decl * prim = try_get_primary_by_prefix(prefix);
if (prim) {
SASSERT(prim->get_arity() == arity);
SASSERT(prim->get_range() == range);
//domain should match as well, but we won't bother checking an array equality
return conv(prim, 0, idx);
func_decl * sym_mux::find_by_decl(func_decl* fdecl, unsigned idx) const {
sym_mux_entry *entry = nullptr;
if (m_entries.find(fdecl, entry)) {
ensure_capacity(*entry, idx+1);
return entry->m_variants.get(idx);
}
decl_vector syms;
create_tuple(prefix, arity, domain, range, idx + 1, syms);
return syms[idx];
return nullptr;
}
bool sym_mux::is_muxed_lit(expr * e, unsigned idx) const
{
if (!is_app(e)) { return false; }
app * a = to_app(e);
if (m.is_not(a) && is_app(a->get_arg(0))) {
a = to_app(a->get_arg(0));
func_decl * sym_mux::shift_decl(func_decl * decl,
unsigned src_idx, unsigned tgt_idx) const {
std::pair<sym_mux_entry*,unsigned> entry;
if (m_muxes.find(decl, entry)) {
SASSERT(entry.second == src_idx);
ensure_capacity(*entry.first, tgt_idx + 1);
return entry.first->m_variants.get(tgt_idx);
}
return is_muxed(a->get_decl());
UNREACHABLE();
return nullptr;
}
namespace {
struct formula_checker {
formula_checker(const sym_mux & parent, unsigned idx) :
m_parent(parent), m_idx(idx), m_found(false) {}
struct sym_mux::formula_checker {
formula_checker(const sym_mux & parent, bool all, unsigned idx) :
m_parent(parent), m_all(all), m_idx(idx),
m_found_what_needed(false)
{
}
void operator()(expr * e)
{
if (m_found_what_needed || !is_app(e)) { return; }
void operator()(expr * e) {
if (m_found || !is_app(e)) { return; }
func_decl * sym = to_app(e)->get_decl();
unsigned sym_idx;
if (!m_parent.try_get_index(sym, sym_idx)) { return; }
if (!m_parent.find_idx(sym, sym_idx)) { return; }
bool have_idx = sym_idx == m_idx;
if (m_all ? (!have_idx) : have_idx) {
m_found_what_needed = true;
}
m_found = !have_idx;
}
bool all_have_idx() const
{
SASSERT(m_all); //we were looking for the queried property
return !m_found_what_needed;
}
bool some_with_idx() const
{
SASSERT(!m_all); //we were looking for the queried property
return m_found_what_needed;
}
bool all_have_idx() const {return !m_found;}
private:
const sym_mux & m_parent;
bool m_all;
unsigned m_idx;
/**
If we check whether all muxed symbols are of given index, we look for
counter-examples, checking whether form contains a muxed symbol of an index,
we look for symbol of index m_idx.
*/
bool m_found_what_needed;
bool m_found;
};
bool sym_mux::contains(expr * e, unsigned idx) const
{
formula_checker chck(*this, false, idx);
for_each_expr(chck, m_visited, e);
m_visited.reset();
return chck.some_with_idx();
}
bool sym_mux::is_homogenous_formula(expr * e, unsigned idx) const
{
formula_checker chck(*this, true, idx);
for_each_expr(chck, m_visited, e);
m_visited.reset();
return chck.all_have_idx();
bool sym_mux::is_homogenous_formula(expr * e, unsigned idx) const {
expr_mark visited;
formula_checker fck(*this, idx);
for_each_expr(fck, visited, e);
return fck.all_have_idx();
}
bool sym_mux::is_homogenous(const expr_ref_vector & vect, unsigned idx) const
{
expr * const * begin = vect.c_ptr();
expr * const * end = begin + vect.size();
for (expr * const * it = begin; it != end; it++) {
if (!is_homogenous_formula(*it, idx)) {
return false;
}
}
return true;
}
class sym_mux::index_collector {
sym_mux const& m_parent;
svector<bool> m_indices;
public:
index_collector(sym_mux const& s):
m_parent(s) {}
void operator()(expr * e)
{
if (is_app(e)) {
func_decl * sym = to_app(e)->get_decl();
unsigned idx;
if (m_parent.try_get_index(sym, idx)) {
SASSERT(idx > 0);
--idx;
if (m_indices.size() <= idx) {
m_indices.resize(idx + 1, false);
}
m_indices[idx] = true;
}
}
}
void extract(unsigned_vector& indices)
{
for (unsigned i = 0; i < m_indices.size(); ++i) {
if (m_indices[i]) {
indices.push_back(i);
}
}
}
};
void sym_mux::collect_indices(expr* e, unsigned_vector& indices) const
{
indices.reset();
index_collector collector(*this);
for_each_expr(collector, m_visited, e);
m_visited.reset();
collector.extract(indices);
}
class sym_mux::variable_collector {
sym_mux const& m_parent;
vector<ptr_vector<app> >& m_vars;
public:
variable_collector(sym_mux const& s, vector<ptr_vector<app> >& vars):
m_parent(s), m_vars(vars) {}
void operator()(expr * e)
{
if (is_app(e)) {
func_decl * sym = to_app(e)->get_decl();
unsigned idx;
if (m_parent.try_get_index(sym, idx)) {
SASSERT(idx > 0);
--idx;
if (m_vars.size() <= idx) {
m_vars.resize(idx + 1, ptr_vector<app>());
}
m_vars[idx].push_back(to_app(e));
}
}
}
};
void sym_mux::collect_variables(expr* e, vector<ptr_vector<app> >& vars) const
{
vars.reset();
variable_collector collector(*this, vars);
for_each_expr(collector, m_visited, e);
m_visited.reset();
}
class sym_mux::hmg_checker {
const sym_mux & m_parent;
bool m_found_idx;
unsigned m_idx;
bool m_multiple_indexes;
public:
hmg_checker(const sym_mux & parent) :
m_parent(parent), m_found_idx(false), m_multiple_indexes(false)
{
}
void operator()(expr * e)
{
if (m_multiple_indexes || !is_app(e)) { return; }
func_decl * sym = to_app(e)->get_decl();
unsigned sym_idx;
if (!m_parent.try_get_index(sym, sym_idx)) { return; }
if (!m_found_idx) {
m_found_idx = true;
m_idx = sym_idx;
return;
}
if (m_idx == sym_idx) { return; }
m_multiple_indexes = true;
}
bool has_multiple_indexes() const
{
return m_multiple_indexes;
}
};
bool sym_mux::is_homogenous_formula(expr * e) const
{
hmg_checker chck(*this);
for_each_expr(chck, m_visited, e);
m_visited.reset();
return !chck.has_multiple_indexes();
}
struct sym_mux::conv_rewriter_cfg : public default_rewriter_cfg {
namespace {
struct conv_rewriter_cfg : public default_rewriter_cfg {
private:
ast_manager & m;
const sym_mux & m_parent;
unsigned m_from_idx;
unsigned m_to_idx;
bool m_homogenous;
expr_ref_vector m_pinned;
public:
conv_rewriter_cfg(const sym_mux & parent, unsigned from_idx, unsigned to_idx, bool homogenous)
conv_rewriter_cfg(const sym_mux & parent, unsigned from_idx,
unsigned to_idx, bool homogenous)
: m(parent.get_manager()),
m_parent(parent),
m_from_idx(from_idx),
m_to_idx(to_idx),
m_homogenous(homogenous) {}
m_homogenous(homogenous), m_pinned(m) {(void) m_homogenous;}
bool get_subst(expr * s, expr * & t, proof * & t_pr)
{
@ -368,241 +148,23 @@ public:
app * a = to_app(s);
func_decl * sym = a->get_decl();
if (!m_parent.has_index(sym, m_from_idx)) {
(void) m_homogenous;
SASSERT(!m_homogenous || !m_parent.is_muxed(sym));
return false;
}
func_decl * tgt = m_parent.conv(sym, m_from_idx, m_to_idx);
func_decl * tgt = m_parent.shift_decl(sym, m_from_idx, m_to_idx);
t = m.mk_app(tgt, a->get_args());
m_pinned.push_back(t);
return true;
}
};
void sym_mux::conv_formula(expr * f, unsigned src_idx, unsigned tgt_idx, expr_ref & res, bool homogenous) const
{
if (src_idx == tgt_idx) {
res = f;
return;
}
conv_rewriter_cfg r_cfg(*this, src_idx, tgt_idx, homogenous);
rewriter_tpl<conv_rewriter_cfg> rwr(m, false, r_cfg);
rwr(f, res);
}
struct sym_mux::shifting_rewriter_cfg : public default_rewriter_cfg {
private:
ast_manager & m;
const sym_mux & m_parent;
int m_shift;
public:
shifting_rewriter_cfg(const sym_mux & parent, int shift)
: m(parent.get_manager()),
m_parent(parent),
m_shift(shift) {}
bool get_subst(expr * s, expr * & t, proof * & t_pr)
{
if (!is_app(s)) { return false; }
app * a = to_app(s);
func_decl * sym = a->get_decl();
unsigned idx;
if (!m_parent.try_get_index(sym, idx)) {
return false;
}
SASSERT(static_cast<int>(idx) + m_shift >= 0);
func_decl * tgt = m_parent.conv(sym, idx, idx + m_shift);
t = m.mk_app(tgt, a->get_args());
return true;
}
};
void sym_mux::shift_formula(expr * f, int dist, expr_ref & res) const
{
if (dist == 0) {
res = f;
return;
}
shifting_rewriter_cfg r_cfg(*this, dist);
rewriter_tpl<shifting_rewriter_cfg> rwr(m, false, r_cfg);
rwr(f, res);
}
void sym_mux::conv_formula_vector(const expr_ref_vector & vect, unsigned src_idx, unsigned tgt_idx,
expr_ref_vector & res) const
{
res.reset();
expr * const * begin = vect.c_ptr();
expr * const * end = begin + vect.size();
for (expr * const * it = begin; it != end; it++) {
expr_ref converted(m);
conv_formula(*it, src_idx, tgt_idx, converted);
res.push_back(converted);
void sym_mux::shift_expr(expr * f, unsigned src_idx, unsigned tgt_idx,
expr_ref & res, bool homogenous) const {
if (src_idx == tgt_idx) {res = f;}
else {
conv_rewriter_cfg r_cfg(*this, src_idx, tgt_idx, homogenous);
rewriter_tpl<conv_rewriter_cfg> rwr(m, false, r_cfg);
rwr(f, res);
}
}
void sym_mux::filter_idx(expr_ref_vector & vect, unsigned idx) const
{
unsigned i = 0;
while (i < vect.size()) {
expr* e = vect[i].get();
if (contains(e, idx) && is_homogenous_formula(e, idx)) {
i++;
} else {
//we don't allow mixing states inside vector elements
SASSERT(!contains(e, idx));
vect[i] = vect.back();
vect.pop_back();
}
}
}
void sym_mux::partition_o_idx(
expr_ref_vector const& lits,
expr_ref_vector& o_lits,
expr_ref_vector& other, unsigned idx) const
{
for (unsigned i = 0; i < lits.size(); ++i) {
if (contains(lits[i], idx) && is_homogenous_formula(lits[i], idx)) {
o_lits.push_back(lits[i]);
} else {
other.push_back(lits[i]);
}
}
}
class sym_mux::nonmodel_sym_checker {
const sym_mux & m_parent;
bool m_found;
public:
nonmodel_sym_checker(const sym_mux & parent) :
m_parent(parent), m_found(false)
{
}
void operator()(expr * e)
{
if (m_found || !is_app(e)) { return; }
func_decl * sym = to_app(e)->get_decl();
if (m_parent.is_non_model_sym(sym)) {
m_found = true;
}
}
bool found() const
{
return m_found;
}
};
bool sym_mux::has_nonmodel_symbol(expr * e) const
{
nonmodel_sym_checker chck(*this);
for_each_expr(chck, e);
return chck.found();
}
void sym_mux::filter_non_model_lits(expr_ref_vector & vect) const
{
unsigned i = 0;
while (i < vect.size()) {
if (!has_nonmodel_symbol(vect[i].get())) {
i++;
continue;
}
vect[i] = vect.back();
vect.pop_back();
}
}
class sym_mux::decl_idx_comparator {
const sym_mux & m_parent;
public:
decl_idx_comparator(const sym_mux & parent)
: m_parent(parent)
{ }
bool operator()(func_decl * sym1, func_decl * sym2)
{
unsigned idx1, idx2;
if (!m_parent.try_get_index(sym1, idx1)) { idx1 = UINT_MAX; }
if (!m_parent.try_get_index(sym2, idx2)) { idx2 = UINT_MAX; }
if (idx1 != idx2) { return idx1 < idx2; }
return lt(sym1->get_name(), sym2->get_name());
}
};
std::string sym_mux::pp_model(const model_core & mdl) const
{
decl_vector consts;
unsigned sz = mdl.get_num_constants();
for (unsigned i = 0; i < sz; i++) {
func_decl * d = mdl.get_constant(i);
consts.push_back(d);
}
std::sort(consts.begin(), consts.end(), decl_idx_comparator(*this));
std::stringstream res;
decl_vector::iterator end = consts.end();
for (decl_vector::iterator it = consts.begin(); it != end; it++) {
func_decl * d = *it;
std::string name = d->get_name().str();
const char * arrow = " -> ";
res << name << arrow;
unsigned indent = static_cast<unsigned>(name.length() + strlen(arrow));
res << mk_pp(mdl.get_const_interp(d), m, indent) << "\n";
if (it + 1 != end) {
unsigned idx1, idx2;
if (!try_get_index(*it, idx1)) { idx1 = UINT_MAX; }
if (!try_get_index(*(it + 1), idx2)) { idx2 = UINT_MAX; }
if (idx1 != idx2) { res << "\n"; }
}
}
return res.str();
}
#if 0
class sym_mux::index_renamer_cfg : public default_rewriter_cfg {
const sym_mux & m_parent;
unsigned m_idx;
public:
index_renamer_cfg(const sym_mux & p, unsigned idx) : m_parent(p), m_idx(idx) {}
bool get_subst(expr * s, expr * & t, proof * & t_pr)
{
if (!is_app(s)) { return false; }
app * a = to_app(s);
if (a->get_family_id() != null_family_id) {
return false;
}
func_decl * sym = a->get_decl();
unsigned idx;
if (!m_parent.try_get_index(sym, idx)) {
return false;
}
if (m_idx == idx) {
return false;
}
ast_manager& m = m_parent.get_manager();
symbol name = symbol((sym->get_name().str() + "!").c_str());
func_decl * tgt = m.mk_func_decl(name, sym->get_arity(), sym->get_domain(), sym->get_range());
t = m.mk_app(tgt, a->get_num_args(), a->get_args());
return true;
}
};
#endif

238
src/muz/spacer/spacer_sym_mux.h
View file

@ -1,5 +1,5 @@
/*++
Copyright (c) 2011 Microsoft Corporation
Copyright (c) 2018 Arie Gurfinkel and Microsoft Corporation
Module Name:
@ -7,10 +7,12 @@ Module Name:
Abstract:
A symbol multiplexer that helps with having multiple versions of each of a set of symbols.
A symbol multiplexer that helps with having multiple versions of
each of a set of symbols.
Author:
Arie Gurfinkel
Krystof Hoder (t-khoder) 2011-9-8.
Revision History:
@ -20,236 +22,72 @@ Revision History:
#ifndef _SYM_MUX_H_
#define _SYM_MUX_H_
#include <string>
#include "ast/ast.h"
#include "util/map.h"
#include "util/vector.h"
#include <vector>
class model_core;
namespace spacer {
class sym_mux {
public:
typedef ptr_vector<app> app_vector;
typedef ptr_vector<func_decl> decl_vector;
private:
typedef obj_map<func_decl, unsigned> sym2u;
typedef obj_map<func_decl, decl_vector> sym2dv;
typedef obj_map<func_decl, func_decl *> sym2sym;
typedef obj_map<func_decl, func_decl *> sym2pred;
typedef hashtable<symbol, symbol_hash_proc, symbol_eq_proc> symbols;
class sym_mux_entry {
public:
func_decl_ref m_main;
func_decl_ref_vector m_variants;
sym_mux_entry(ast_manager &m) : m_main(m), m_variants(m) {};
};
ast_manager & m;
mutable ast_ref_vector m_ref_holder;
mutable expr_mark m_visited;
typedef obj_map<func_decl, sym_mux_entry*> decl2entry_map;
typedef obj_map<func_decl, std::pair<sym_mux_entry*, unsigned> > mux2entry_map;
mutable unsigned m_next_sym_suffix_idx;
mutable symbols m_used_suffixes;
/** Here we have default suffixes for each of the variants */
mutable std::vector<std::string> m_suffixes;
ast_manager &m;
mutable decl2entry_map m_entries;
mutable mux2entry_map m_muxes;
func_decl_ref mk_variant(func_decl *fdecl, unsigned i) const;
void ensure_capacity(sym_mux_entry &entry, unsigned sz) const;
/**
Primary symbol is the 0-th variant. This member maps from primary symbol
to vector of all its variants (including the primary variant).
*/
sym2dv m_prim2all;
/**
For each symbol contains its variant index
*/
mutable sym2u m_sym2idx;
/**
For each symbol contains its primary variant
*/
mutable sym2sym m_sym2prim;
/**
Maps prefixes passed to the create_tuple to
the primary symbol created from it.
*/
sym2pred m_prefix2prim;
/**
Maps pripary symbols to prefixes that were used to create them.
*/
sym2sym m_prim2prefix;
decl_vector m_prim_preds;
obj_hashtable<func_decl> m_non_model_syms;
struct formula_checker;
struct conv_rewriter_cfg;
struct shifting_rewriter_cfg;
class decl_idx_comparator;
class hmg_checker;
class nonmodel_sym_checker;
class index_renamer_cfg;
class index_collector;
class variable_collector;
std::string get_suffix(unsigned i) const;
void ensure_tuple_size(func_decl * prim, unsigned sz) const;
expr_ref isolate_o_idx(expr* e, unsigned idx) const;
public:
sym_mux(ast_manager & m, const std::vector<std::string> & suffixes);
sym_mux(ast_manager & m);
~sym_mux();
ast_manager & get_manager() const { return m; }
bool is_muxed(func_decl * sym) const { return m_sym2idx.contains(sym); }
bool try_get_index(func_decl * sym, unsigned & idx) const
{
return m_sym2idx.find(sym, idx);
}
void register_decl(func_decl *fdecl);
bool find_idx(func_decl * sym, unsigned & idx) const;
bool has_index(func_decl * sym, unsigned idx) const
{
unsigned actual_idx;
return try_get_index(sym, actual_idx) && idx == actual_idx;
}
{unsigned v; return find_idx(sym, v) && idx == v;}
/** Return primary symbol. sym must be muxed. */
func_decl * get_primary(func_decl * sym) const
{
func_decl * prim;
TRUSTME(m_sym2prim.find(sym, prim));
return prim;
}
bool is_muxed(func_decl *fdecl) const {return m_muxes.contains(fdecl);}
/**
Return primary symbol created from prefix, or 0 if the prefix was never used.
\brief Return symbol created from prefix, or 0 if the prefix
was never used.
*/
func_decl * try_get_primary_by_prefix(func_decl* prefix) const
{
func_decl * res;
if(!m_prefix2prim.find(prefix, res)) {
return nullptr;
}
return res;
}
func_decl * find_by_decl(func_decl* fdecl, unsigned idx) const;
/**
Return symbol created from prefix, or 0 if the prefix was never used.
*/
func_decl * try_get_by_prefix(func_decl* prefix, unsigned idx) const
{
func_decl * prim = try_get_primary_by_prefix(prefix);
if(!prim) {
return nullptr;
}
return conv(prim, 0, idx);
}
/**
Marks symbol as non-model which means it will not appear in models collected by
get_muxed_cube_from_model function.
This is to take care of auxiliary symbols introduced by the disjunction relations
to relativize lemmas coming from disjuncts.
*/
void mark_as_non_model(func_decl * sym)
{
SASSERT(is_muxed(sym));
m_non_model_syms.insert(get_primary(sym));
}
func_decl * get_or_create_symbol_by_prefix(func_decl* prefix, unsigned idx,
unsigned arity, sort * const * domain, sort * range);
bool is_muxed_lit(expr * e, unsigned idx) const;
bool is_non_model_sym(func_decl * s) const
{
return is_muxed(s) && m_non_model_syms.contains(get_primary(s));
}
/**
Create a multiplexed tuple of propositional constants.
Symbols may be suplied in the tuple vector,
those beyond the size of the array and those with corresponding positions
assigned to zero will be created using prefix.
Tuple length must be at least one.
*/
void create_tuple(func_decl* prefix, unsigned arity, sort * const * domain, sort * range,
unsigned tuple_length, decl_vector & tuple);
/**
Return true if the only multiplexed symbols which e contains are of index idx.
\brief Return true if the only multiplexed symbols which e contains are
of index idx.
*/
bool is_homogenous_formula(expr * e, unsigned idx) const;
bool is_homogenous(const expr_ref_vector & vect, unsigned idx) const;
/**
Return true if all multiplexed symbols which e contains are of one index.
*/
bool is_homogenous_formula(expr * e) const;
/**
Return true if expression e contains a muxed symbol of index idx.
*/
bool contains(expr * e, unsigned idx) const;
/**
Collect indices used in expression.
*/
void collect_indices(expr* e, unsigned_vector& indices) const;
/**
Collect used variables of each index.
*/
void collect_variables(expr* e, vector<ptr_vector<app> >& vars) const;
/**
Convert symbol sym which has to be of src_idx variant into variant tgt_idx.
*/
func_decl * conv(func_decl * sym, unsigned src_idx, unsigned tgt_idx) const;
/**
Convert src_idx symbols in formula f variant into tgt_idx.
If homogenous is true, formula cannot contain symbols of other variants.
\brief Convert symbol sym which has to be of src_idx variant
into variant tgt_idx.
*/
void conv_formula(expr * f, unsigned src_idx, unsigned tgt_idx, expr_ref & res, bool homogenous = true) const;
void conv_formula_vector(const expr_ref_vector & vect, unsigned src_idx, unsigned tgt_idx,
expr_ref_vector & res) const;
func_decl * shift_decl(func_decl * sym, unsigned src_idx, unsigned tgt_idx) const;
/**
Shifts the muxed symbols in f by dist. Dist can be negative, but it should never shift
symbol index to a negative value.
\brief Convert src_idx symbols in formula f variant into
tgt_idx. If homogenous is true, formula cannot contain symbols
of other variants.
*/
void shift_formula(expr * f, int dist, expr_ref & res) const;
void shift_expr(expr * f, unsigned src_idx, unsigned tgt_idx,
expr_ref & res, bool homogenous = true) const;
/**
Remove from vect literals (atoms or negations of atoms) of symbols
that contain multiplexed symbols with indexes other than idx.
Each of the literals can contain only symbols multiplexed with one index
(this trivially holds if the literals are propositional).
Order of elements in vect may be modified by this function
*/
void filter_idx(expr_ref_vector & vect, unsigned idx) const;
/**
Partition literals into o_literals and others.
*/
void partition_o_idx(expr_ref_vector const& lits,
expr_ref_vector& o_lits,
expr_ref_vector& other, unsigned idx) const;
bool has_nonmodel_symbol(expr * e) const;
void filter_non_model_lits(expr_ref_vector & vect) const;
func_decl * const * begin_prim_preds() const { return m_prim_preds.begin(); }
func_decl * const * end_prim_preds() const { return m_prim_preds.end(); }
void get_muxed_cube_from_model(const model_core & model, expr_ref_vector & res) const;
std::string pp_model(const model_core & mdl) const;
};
}

315
src/muz/spacer/spacer_unsat_core_learner.cpp
View file

@ -17,111 +17,47 @@ Revision History:
--*/
#include <unordered_map>
#include "ast/for_each_expr.h"
#include "ast/proofs/proof_utils.h"
#include "muz/spacer/spacer_unsat_core_learner.h"
#include "muz/spacer/spacer_unsat_core_plugin.h"
#include "ast/for_each_expr.h"
namespace spacer
{
#include "muz/spacer/spacer_iuc_proof.h"
#include "muz/spacer/spacer_util.h"
unsat_core_learner::~unsat_core_learner()
{
namespace spacer {
unsat_core_learner::~unsat_core_learner() {
std::for_each(m_plugins.begin(), m_plugins.end(), delete_proc<unsat_core_plugin>());
}
void unsat_core_learner::register_plugin(unsat_core_plugin* plugin)
{
void unsat_core_learner::register_plugin(unsat_core_plugin* plugin) {
m_plugins.push_back(plugin);
}
void unsat_core_learner::compute_unsat_core(proof *root, expr_set& asserted_b, expr_ref_vector& unsat_core)
{
// transform proof in order to get a proof which is better suited for unsat-core-extraction
proof_ref pr(root, m);
reduce_hypotheses(pr);
STRACE("spacer.unsat_core_learner",
verbose_stream() << "Reduced proof:\n" << mk_ismt2_pp(pr, m) << "\n";
);
// compute symbols occurring in B
collect_symbols_b(asserted_b);
void unsat_core_learner::compute_unsat_core(expr_ref_vector& unsat_core) {
// traverse proof
proof_post_order it(root, m);
while (it.hasNext())
{
proof_post_order it(m_pr.get(), m);
while (it.hasNext()) {
proof* currentNode = it.next();
if (m.get_num_parents(currentNode) == 0)
{
switch(currentNode->get_decl_kind())
{
case PR_ASSERTED: // currentNode is an axiom
{
if (asserted_b.contains(m.get_fact(currentNode)))
{
m_b_mark.mark(currentNode, true);
}
else
{
m_a_mark.mark(currentNode, true);
}
break;
}
// currentNode is a hypothesis:
case PR_HYPOTHESIS:
{
m_h_mark.mark(currentNode, true);
break;
}
default:
{
break;
}
}
}
else
{
// collect from parents whether derivation of current node contains A-axioms, B-axioms and hypothesis
bool need_to_mark_a = false;
bool need_to_mark_b = false;
bool need_to_mark_h = false;
if (m.get_num_parents(currentNode) > 0) {
bool need_to_mark_closed = true;
for (unsigned i = 0; i < m.get_num_parents(currentNode); ++i)
{
SASSERT(m.is_proof(currentNode->get_arg(i)));
proof* premise = to_app(currentNode->get_arg(i));
need_to_mark_a = need_to_mark_a || m_a_mark.is_marked(premise);
need_to_mark_b = need_to_mark_b || m_b_mark.is_marked(premise);
need_to_mark_h = need_to_mark_h || m_h_mark.is_marked(premise);
need_to_mark_closed = need_to_mark_closed && (!m_b_mark.is_marked(premise) || m_closed.is_marked(premise));
for (proof* premise : m.get_parents(currentNode)) {
need_to_mark_closed &= (!m_pr.is_b_marked(premise) || m_closed.is_marked(premise));
}
// if current node is application of lemma, we know that all hypothesis are removed
if(currentNode->get_decl_kind() == PR_LEMMA)
{
need_to_mark_h = false;
}
// save results
m_a_mark.mark(currentNode, need_to_mark_a);
m_b_mark.mark(currentNode, need_to_mark_b);
m_h_mark.mark(currentNode, need_to_mark_h);
// save result
m_closed.mark(currentNode, need_to_mark_closed);
}
// we have now collected all necessary information, so we can visit the node
// if the node mixes A-reasoning and B-reasoning and contains non-closed premises
if (m_a_mark.is_marked(currentNode) && m_b_mark.is_marked(currentNode) && !m_closed.is_marked(currentNode))
{
if (m_pr.is_a_marked(currentNode) &&
m_pr.is_b_marked(currentNode) &&
!m_closed.is_marked(currentNode)) {
compute_partial_core(currentNode); // then we need to compute a partial core
// SASSERT(!(m_a_mark.is_marked(currentNode) && m_b_mark.is_marked(currentNode)) || m_closed.is_marked(currentNode)); TODO: doesn't hold anymore if we do the mincut-thing!
}
}
@ -130,226 +66,39 @@ void unsat_core_learner::compute_unsat_core(proof *root, expr_set& asserted_b, e
// TODO: remove duplicates from unsat core?
bool debug_proof = false;
if(debug_proof)
{
// print proof for debugging
verbose_stream() << "\n\nProof:\n";
std::unordered_map<unsigned, unsigned> id_to_small_id;
unsigned counter = 0;
proof_post_order it2(root, m);
while (it2.hasNext())
{
proof* currentNode = it2.next();
SASSERT(id_to_small_id.find(currentNode->get_id()) == id_to_small_id.end());
id_to_small_id.insert(std::make_pair(currentNode->get_id(), counter));
verbose_stream() << counter << " ";
verbose_stream() << "[";
if (is_a_marked(currentNode))
{
verbose_stream() << "a";
}
if (is_b_marked(currentNode))
{
verbose_stream() << "b";
}
if (is_h_marked(currentNode))
{
verbose_stream() << "h";
}
if (is_closed(currentNode))
{
verbose_stream() << "c";
}
verbose_stream() << "] ";
if (m.get_num_parents(currentNode) == 0)
{
switch (currentNode->get_decl_kind())
{
case PR_ASSERTED:
verbose_stream() << "asserted";
break;
case PR_HYPOTHESIS:
verbose_stream() << "hypothesis";
break;
default:
verbose_stream() << "unknown axiom-type";
break;
}
}
else
{
if (currentNode->get_decl_kind() == PR_LEMMA)
{
verbose_stream() << "lemma";
}
else if (currentNode->get_decl_kind() == PR_TH_LEMMA)
{
verbose_stream() << "th_lemma";
func_decl* d = currentNode->get_decl();
symbol sym;
if (d->get_num_parameters() >= 2 && // the Farkas coefficients are saved in the parameters of step
d->get_parameter(0).is_symbol(sym) && sym == "arith" && // the first two parameters are "arith", "farkas",
d->get_parameter(1).is_symbol(sym) && sym == "farkas")
{
verbose_stream() << "(farkas)";
}
else
{
verbose_stream() << "(other)";
}
}
else
{
verbose_stream() << "step";
}
verbose_stream() << " from ";
for (int i = m.get_num_parents(currentNode) - 1; i >= 0 ; --i)
{
proof* premise = to_app(currentNode->get_arg(i));
unsigned premise_small_id = id_to_small_id[premise->get_id()];
if (i > 0)
{
verbose_stream() << premise_small_id << ", ";
}
else
{
verbose_stream() << premise_small_id;
}
}
}
if (currentNode->get_decl_kind() == PR_TH_LEMMA || (is_a_marked(currentNode) && is_b_marked(currentNode)) || is_h_marked(currentNode) || (!is_a_marked(currentNode) && !is_b_marked(currentNode)))
{
verbose_stream() << std::endl;
}
else
{
verbose_stream() << ": " << mk_pp(m.get_fact(currentNode), m) << std::endl;
}
++counter;
}
}
// move all lemmas into vector
for (expr* const* it = m_unsat_core.begin(); it != m_unsat_core.end(); ++it)
{
unsat_core.push_back(*it);
for (expr* e : m_unsat_core) {
unsat_core.push_back(e);
}
}
void unsat_core_learner::compute_partial_core(proof* step)
{
for (unsat_core_plugin** it=m_plugins.begin(), **end = m_plugins.end (); it != end && !m_closed.is_marked(step); ++it)
{
unsat_core_plugin* plugin = *it;
void unsat_core_learner::compute_partial_core(proof* step) {
for (unsat_core_plugin* plugin : m_plugins) {
if (m_closed.is_marked(step)) break;
plugin->compute_partial_core(step);
}
}
void unsat_core_learner::finalize()
{
for (unsat_core_plugin** it=m_plugins.begin(); it != m_plugins.end(); ++it)
{
unsat_core_plugin* plugin = *it;
void unsat_core_learner::finalize() {
for (unsat_core_plugin* plugin : m_plugins) {
plugin->finalize();
}
}
bool unsat_core_learner::is_a_marked(proof* p)
{
return m_a_mark.is_marked(p);
}
bool unsat_core_learner::is_b_marked(proof* p)
{
return m_b_mark.is_marked(p);
}
bool unsat_core_learner::is_h_marked(proof* p)
{
return m_h_mark.is_marked(p);
}
bool unsat_core_learner::is_closed(proof*p)
{
bool unsat_core_learner::is_closed(proof* p) {
return m_closed.is_marked(p);
}
void unsat_core_learner::set_closed(proof* p, bool value)
{
void unsat_core_learner::set_closed(proof* p, bool value) {
m_closed.mark(p, value);
}
void unsat_core_learner::add_lemma_to_core(expr* lemma)
{
m_unsat_core.push_back(lemma);
}
class collect_pure_proc {
func_decl_set& m_symbs;
public:
collect_pure_proc(func_decl_set& s):m_symbs(s) {}
void operator()(app* a) {
if (a->get_family_id() == null_family_id) {
m_symbs.insert(a->get_decl());
}
}
void operator()(var*) {}
void operator()(quantifier*) {}
};
void unsat_core_learner::collect_symbols_b(const expr_set& axioms_b)
{
expr_mark visited;
collect_pure_proc proc(m_symbols_b);
for (expr_set::iterator it = axioms_b.begin(); it != axioms_b.end(); ++it)
{
for_each_expr(proc, visited, *it);
}
bool unsat_core_learner::is_b_open(proof *p) {
return m_pr.is_b_marked(p) && !is_closed (p);
}
class is_pure_expr_proc {
func_decl_set const& m_symbs;
array_util m_au;
public:
struct non_pure {};
is_pure_expr_proc(func_decl_set const& s, ast_manager& m):
m_symbs(s),
m_au (m)
{}
void operator()(app* a) {
if (a->get_family_id() == null_family_id) {
if (!m_symbs.contains(a->get_decl())) {
throw non_pure();
}
}
else if (a->get_family_id () == m_au.get_family_id () &&
a->is_app_of (a->get_family_id (), OP_ARRAY_EXT)) {
throw non_pure();
}
}
void operator()(var*) {}
void operator()(quantifier*) {}
};
bool unsat_core_learner::only_contains_symbols_b(expr* expr) const
{
is_pure_expr_proc proc(m_symbols_b, m);
try {
for_each_expr(proc, expr);
}
catch (is_pure_expr_proc::non_pure)
{
return false;
}
return true;
void unsat_core_learner::add_lemma_to_core(expr* lemma) {
m_unsat_core.push_back(lemma);
}
}

50
src/muz/spacer/spacer_unsat_core_learner.h
View file

@ -6,7 +6,8 @@ Module Name:
spacer_unsat_core_learner.h
Abstract:
itp cores
itp cores
Author:
Bernhard Gleiss
@ -20,21 +21,23 @@ Revision History:
#include "ast/ast.h"
#include "muz/spacer/spacer_util.h"
#include "ast/proofs/proof_utils.h"
#include "muz/spacer/spacer_proof_utils.h"
namespace spacer {
class unsat_core_plugin;
class unsat_core_learner
{
class iuc_proof;
class unsat_core_learner {
typedef obj_hashtable<expr> expr_set;
public:
unsat_core_learner(ast_manager& m) : m(m), m_unsat_core(m) {};
unsat_core_learner(ast_manager& m, iuc_proof& pr) :
m(m), m_pr(pr), m_unsat_core(m) {};
virtual ~unsat_core_learner();
ast_manager& m;
iuc_proof& m_pr;
/*
* register a plugin for computation of partial unsat cores
@ -45,51 +48,33 @@ namespace spacer {
/*
* compute unsat core using the registered unsat-core-plugins
*/
void compute_unsat_core(proof* root, expr_set& asserted_b, expr_ref_vector& unsat_core);
void compute_unsat_core(expr_ref_vector& unsat_core);
/*
* getter/setter methods for data structures exposed to plugins
* the following invariants can be assumed and need to be maintained by the plugins:
* - a node is a-marked iff it is derived using at least one asserted proof step from A.
* - a node is b-marked iff its derivation contains no asserted proof steps from A and
* no hypothesis (with the additional complication that lemmas conceptually remove hypothesis)
* - a node is h-marked, iff it is derived using at least one hypothesis
* the following invariant can be assumed and need to be maintained by the plugins:
* - a node is closed, iff it has already been interpolated, i.e. its contribution is
* already covered by the unsat-core.
*/
bool is_a_marked(proof* p);
bool is_b_marked(proof* p);
bool is_h_marked(proof* p);
bool is_closed(proof* p);
void set_closed(proof* p, bool value);
bool is_b_open (proof *p);
/*
* adds a lemma to the unsat core
*/
void add_lemma_to_core(expr* lemma);
/*
* helper method, which can be used by plugins
* returns true iff all symbols of expr occur in some b-asserted formula.
* must only be called after a call to collect_symbols_b.
*/
bool only_contains_symbols_b(expr* expr) const;
bool is_b_pure (proof *p)
{return !is_h_marked (p) && only_contains_symbols_b (m.get_fact (p));}
bool is_b_open (proof *p)
{ return is_b_marked (p) && !is_closed (p); }
private:
ptr_vector<unsat_core_plugin> m_plugins;
func_decl_set m_symbols_b; // symbols, which occur in any b-asserted formula
void collect_symbols_b(const expr_set& axioms_b);
ast_mark m_a_mark;
ast_mark m_b_mark;
ast_mark m_h_mark;
ast_mark m_closed;
expr_ref_vector m_unsat_core; // collects the lemmas of the unsat-core, will at the end be inserted into unsat_core.
/*
* collects the lemmas of the unsat-core
* will at the end be inserted into unsat_core.
*/
expr_ref_vector m_unsat_core;
/*
* computes partial core for step by delegating computation to plugins
@ -101,7 +86,6 @@ namespace spacer {
*/
void finalize();
};
}
#endif

778
src/muz/spacer/spacer_unsat_core_plugin.cpp
View file

@ -6,7 +6,7 @@ Module Name:
spacer_unsat_core_plugin.cpp
Abstract:
plugin for itp cores
plugin for itp cores
Author:
Bernhard Gleiss
@ -30,311 +30,248 @@ Revision History:
#include "muz/spacer/spacer_matrix.h"
#include "muz/spacer/spacer_unsat_core_plugin.h"
#include "muz/spacer/spacer_unsat_core_learner.h"
#include "muz/spacer/spacer_iuc_proof.h"
namespace spacer
{
namespace spacer {
void unsat_core_plugin_lemma::compute_partial_core(proof* step)
{
SASSERT(m_learner.is_a_marked(step));
SASSERT(m_learner.is_b_marked(step));
for (unsigned i = 0; i < m_learner.m.get_num_parents(step); ++i)
unsat_core_plugin::unsat_core_plugin(unsat_core_learner& learner):
m(learner.m), m_learner(learner) {};
void unsat_core_plugin_lemma::compute_partial_core(proof* step) {
SASSERT(m_learner.m_pr.is_a_marked(step));
SASSERT(m_learner.m_pr.is_b_marked(step));
for (proof* premise : m.get_parents(step)) {
if (m_learner.is_b_open (premise)) {
// by IH, premises that are AB marked are already closed
SASSERT(!m_learner.m_pr.is_a_marked(premise));
add_lowest_split_to_core(premise);
}
}
m_learner.set_closed(step, true);
}
void unsat_core_plugin_lemma::add_lowest_split_to_core(proof* step) const
{
SASSERT(m_learner.m.is_proof(step->get_arg(i)));
proof* premise = to_app(step->get_arg(i));
if (m_learner.is_b_open (premise))
{
// by IH, premises that are AB marked are already closed
SASSERT(!m_learner.is_a_marked(premise));
add_lowest_split_to_core(premise);
SASSERT(m_learner.is_b_open(step));
ptr_buffer<proof> todo;
todo.push_back(step);
while (!todo.empty()) {
proof* pf = todo.back();
todo.pop_back();
// if current step hasn't been processed,
if (!m_learner.is_closed(pf)) {
m_learner.set_closed(pf, true);
// the step is b-marked and not closed.
// by I.H. the step must be already visited
// so if it is also a-marked, it must be closed
SASSERT(m_learner.m_pr.is_b_marked(pf));
SASSERT(!m_learner.m_pr.is_a_marked(pf));
// the current step needs to be interpolated:
expr* fact = m.get_fact(pf);
// if we trust the current step and we are able to use it
if (m_learner.m_pr.is_b_pure (pf) &&
(m.is_asserted(pf) || is_literal(m, fact))) {
// just add it to the core
m_learner.add_lemma_to_core(fact);
}
// otherwise recurse on premises
else {
for (proof* premise : m.get_parents(pf))
if (m_learner.is_b_open(premise))
todo.push_back(premise);
}
}
}
}
m_learner.set_closed(step, true);
}
void unsat_core_plugin_lemma::add_lowest_split_to_core(proof* step) const
{
SASSERT(m_learner.is_b_open(step));
ast_manager &m = m_learner.m;
ptr_vector<proof> todo;
todo.push_back(step);
while (!todo.empty())
void unsat_core_plugin_farkas_lemma::compute_partial_core(proof* step)
{
proof* pf = todo.back();
todo.pop_back();
// if current step hasn't been processed,
if (!m_learner.is_closed(pf))
{
m_learner.set_closed(pf, true);
// the step is b-marked and not closed.
// by I.H. the step must be already visited
// so if it is also a-marked, it must be closed
SASSERT(m_learner.is_b_marked(pf));
SASSERT(!m_learner.is_a_marked(pf));
// the current step needs to be interpolated:
expr* fact = m_learner.m.get_fact(pf);
// if we trust the current step and we are able to use it
if (m_learner.is_b_pure (pf) &&
(m.is_asserted(pf) || is_literal(m, fact)))
{
// just add it to the core
m_learner.add_lemma_to_core(fact);
SASSERT(m_learner.m_pr.is_a_marked(step));
SASSERT(m_learner.m_pr.is_b_marked(step));
// XXX this assertion should be true so there is no need to check for it
SASSERT (!m_learner.is_closed (step));
func_decl* d = step->get_decl();
symbol sym;
if (!m_learner.is_closed(step) && // if step is not already interpolated
is_farkas_lemma(m, step)) {
// weaker check: d->get_num_parameters() >= m.get_num_parents(step) + 2
SASSERT(d->get_num_parameters() == m.get_num_parents(step) + 2);
SASSERT(m.has_fact(step));
coeff_lits_t coeff_lits;
expr_ref_vector pinned(m);
/* The farkas lemma represents a subproof starting from premise(-set)s A, BNP and BP(ure) and
* ending in a disjunction D. We need to compute the contribution of BP, i.e. a formula, which
* is entailed by BP and together with A and BNP entails D.
*
* Let Fark(F) be the farkas coefficient for F. We can use the fact that
* (A*Fark(A) + BNP*Fark(BNP) + BP*Fark(BP) + (neg D)*Fark(D)) => false. (E1)
* We further have that A+B => C implies (A \land B) => C. (E2)
*
* Alternative 1:
* From (E1) immediately get that BP*Fark(BP) is a solution.
*
* Alternative 2:
* We can rewrite (E2) to rewrite (E1) to
* (BP*Fark(BP)) => (neg(A*Fark(A) + BNP*Fark(BNP) + (neg D)*Fark(D))) (E3)
* and since we can derive (A*Fark(A) + BNP*Fark(BNP) + (neg D)*Fark(D)) from
* A, BNP and D, we also know that it is inconsisent. Therefore
* neg(A*Fark(A) + BNP*Fark(BNP) + (neg D)*Fark(D)) is a solution.
*
* Finally we also need the following workaround:
* 1) Although we know from theory, that the Farkas coefficients are always nonnegative,
* the Farkas coefficients provided by arith_core are sometimes negative (must be a bug)
* as workaround we take the absolute value of the provided coefficients.
*/
parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient
STRACE("spacer.farkas",
verbose_stream() << "Farkas input: "<< "\n";
for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * prem = m.get_parent(step, i);
rational coef = params[i].get_rational();
bool b_pure = m_learner.m_pr.is_b_pure (prem);
verbose_stream() << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m.get_fact(prem), m) << "\n";
}
);
bool can_be_closed = true;
for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * premise = m.get_parent(step, i);
if (m_learner.is_b_open (premise)) {
SASSERT(!m_learner.m_pr.is_a_marked(premise));
if (m_learner.m_pr.is_b_pure (step)) {
if (!m_use_constant_from_a) {
rational coefficient = params[i].get_rational();
coeff_lits.push_back(std::make_pair(abs(coefficient), (app*)m.get_fact(premise)));
}
}
else {
can_be_closed = false;
if (m_use_constant_from_a) {
rational coefficient = params[i].get_rational();
coeff_lits.push_back(std::make_pair(abs(coefficient), (app*)m.get_fact(premise)));
}
}
}
else {
if (m_use_constant_from_a) {
rational coefficient = params[i].get_rational();
coeff_lits.push_back(std::make_pair(abs(coefficient), (app*)m.get_fact(premise)));
}
}
}
// otherwise recurse on premises
else
{
for (unsigned i = 0, sz = m_learner.m.get_num_parents(pf);
i < sz; ++i)
{
SASSERT(m_learner.m.is_proof(pf->get_arg(i)));
proof* premise = m.get_parent (pf, i);
if (m_learner.is_b_open(premise)) {
todo.push_back(premise);
if (m_use_constant_from_a) {
params += m.get_num_parents(step); // point to the first Farkas coefficient, which corresponds to a formula in the conclusion
// the conclusion can either be a single formula or a disjunction of several formulas, we have to deal with both situations
if (m.get_num_parents(step) + 2 < d->get_num_parameters()) {
unsigned num_args = 1;
expr* conclusion = m.get_fact(step);
expr* const* args = &conclusion;
if (m.is_or(conclusion)) {
app* _or = to_app(conclusion);
num_args = _or->get_num_args();
args = _or->get_args();
}
SASSERT(m.get_num_parents(step) + 2 + num_args == d->get_num_parameters());
bool_rewriter brw(m);
for (unsigned i = 0; i < num_args; ++i) {
expr* premise = args[i];
expr_ref negatedPremise(m);
brw.mk_not(premise, negatedPremise);
pinned.push_back(negatedPremise);
rational coefficient = params[i].get_rational();
coeff_lits.push_back(std::make_pair(abs(coefficient), to_app(negatedPremise)));
}
}
}
}
}
}
void unsat_core_plugin_farkas_lemma::compute_partial_core(proof* step)
{
ast_manager &m = m_learner.m;
SASSERT(m_learner.is_a_marked(step));
SASSERT(m_learner.is_b_marked(step));
// XXX this assertion should be true so there is no need to check for it
SASSERT (!m_learner.is_closed (step));
func_decl* d = step->get_decl();
symbol sym;
if(!m_learner.is_closed(step) && // if step is not already interpolated
step->get_decl_kind() == PR_TH_LEMMA && // and step is a Farkas lemma
d->get_num_parameters() >= 2 && // the Farkas coefficients are saved in the parameters of step
d->get_parameter(0).is_symbol(sym) && sym == "arith" && // the first two parameters are "arith", "farkas",
d->get_parameter(1).is_symbol(sym) && sym == "farkas" &&
d->get_num_parameters() >= m_learner.m.get_num_parents(step) + 2) // the following parameters are the Farkas coefficients
{
SASSERT(m_learner.m.has_fact(step));
ptr_vector<app> literals;
vector<rational> coefficients;
/* The farkas lemma represents a subproof starting from premise(-set)s A, BNP and BP(ure) and
* ending in a disjunction D. We need to compute the contribution of BP, i.e. a formula, which
* is entailed by BP and together with A and BNP entails D.
*
* Let Fark(F) be the farkas coefficient for F. We can use the fact that
* (A*Fark(A) + BNP*Fark(BNP) + BP*Fark(BP) + (neg D)*Fark(D)) => false. (E1)
* We further have that A+B => C implies (A \land B) => C. (E2)
*
* Alternative 1:
* From (E1) immediately get that BP*Fark(BP) is a solution.
*
* Alternative 2:
* We can rewrite (E2) to rewrite (E1) to
* (BP*Fark(BP)) => (neg(A*Fark(A) + BNP*Fark(BNP) + (neg D)*Fark(D))) (E3)
* and since we can derive (A*Fark(A) + BNP*Fark(BNP) + (neg D)*Fark(D)) from
* A, BNP and D, we also know that it is inconsisent. Therefore
* neg(A*Fark(A) + BNP*Fark(BNP) + (neg D)*Fark(D)) is a solution.
*
* Finally we also need the following workaround:
* 1) Although we know from theory, that the Farkas coefficients are always nonnegative,
* the Farkas coefficients provided by arith_core are sometimes negative (must be a bug)
* as workaround we take the absolute value of the provided coefficients.
*/
parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient
STRACE("spacer.farkas",
verbose_stream() << "Farkas input: "<< "\n";
for (unsigned i = 0; i < m_learner.m.get_num_parents(step); ++i)
{
SASSERT(m_learner.m.is_proof(step->get_arg(i)));
proof *prem = m.get_parent (step, i);
rational coef;
VERIFY(params[i].is_rational(coef));
bool b_pure = m_learner.is_b_pure (prem);
verbose_stream() << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m_learner.m.get_fact(prem), m_learner.m) << "\n";
}
);
bool can_be_closed = true;
for(unsigned i = 0; i < m.get_num_parents(step); ++i)
{
SASSERT(m_learner.m.is_proof(step->get_arg(i)));
proof * premise = m.get_parent (step, i);
if (m_learner.is_b_open (premise))
{
SASSERT(!m_learner.is_a_marked(premise));
if (m_learner.is_b_pure (step))
{
if (!m_use_constant_from_a)
{
rational coefficient;
VERIFY(params[i].is_rational(coefficient));
literals.push_back(to_app(m_learner.m.get_fact(premise)));
coefficients.push_back(abs(coefficient));
}
}
else
{
can_be_closed = false;
if (m_use_constant_from_a)
{
rational coefficient;
VERIFY(params[i].is_rational(coefficient));
literals.push_back(to_app(m_learner.m.get_fact(premise)));
coefficients.push_back(abs(coefficient));
}
}
}
else
{
if (m_use_constant_from_a)
{
rational coefficient;
VERIFY(params[i].is_rational(coefficient));
literals.push_back(to_app(m_learner.m.get_fact(premise)));
coefficients.push_back(abs(coefficient));
}
// only if all b-premises can be used directly, add the farkas core and close the step
if (can_be_closed) {
m_learner.set_closed(step, true);
expr_ref res = compute_linear_combination(coeff_lits);
m_learner.add_lemma_to_core(res);
}
}
}
if (m_use_constant_from_a)
{
params += m_learner.m.get_num_parents(step); // point to the first Farkas coefficient, which corresponds to a formula in the conclusion
expr_ref unsat_core_plugin_farkas_lemma::compute_linear_combination(const coeff_lits_t& coeff_lits)
{
// the conclusion can either be a single formula or a disjunction of several formulas, we have to deal with both situations
if (m_learner.m.get_num_parents(step) + 2 < d->get_num_parameters())
{
unsigned num_args = 1;
expr* conclusion = m_learner.m.get_fact(step);
expr* const* args = &conclusion;
if (m_learner.m.is_or(conclusion))
{
app* _or = to_app(conclusion);
num_args = _or->get_num_args();
args = _or->get_args();
}
SASSERT(m_learner.m.get_num_parents(step) + 2 + num_args == d->get_num_parameters());
bool_rewriter brw(m_learner.m);
for (unsigned i = 0; i < num_args; ++i)
{
expr* premise = args[i];
expr_ref negatedPremise(m_learner.m);
brw.mk_not(premise, negatedPremise);
literals.push_back(to_app(negatedPremise));
rational coefficient;
VERIFY(params[i].is_rational(coefficient));
coefficients.push_back(abs(coefficient));
}
}
smt::farkas_util util(m);
if (m_use_constant_from_a) {
util.set_split_literals (m_split_literals); // small optimization: if flag m_split_literals is set, then preserve diff constraints
}
// only if all b-premises can be used directly, add the farkas core and close the step
if (can_be_closed)
{
m_learner.set_closed(step, true);
expr_ref res(m_learner.m);
compute_linear_combination(coefficients, literals, res);
m_learner.add_lemma_to_core(res);
for (auto& p : coeff_lits) {
util.add(p.first, p.second);
}
if (m_use_constant_from_a) {
return util.get();
}
else {
return expr_ref(mk_not(m, util.get()), m);
}
}
}
void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rational>& coefficients, const ptr_vector<app>& literals, expr_ref& res)
{
SASSERT(literals.size() == coefficients.size());
ast_manager& m = res.get_manager();
smt::farkas_util util(m);
if (m_use_constant_from_a)
{
util.set_split_literals (m_split_literals); // small optimization: if flag m_split_literals is set, then preserve diff constraints
}
for(unsigned i = 0; i < literals.size(); ++i)
{
util.add(coefficients[i], literals[i]);
}
if (m_use_constant_from_a)
{
res = util.get();
}
else
{
expr_ref negated_linear_combination = util.get();
res = mk_not(m, negated_linear_combination);
}
}
void unsat_core_plugin_farkas_lemma_optimized::compute_partial_core(proof* step)
{
SASSERT(m_learner.is_a_marked(step));
SASSERT(m_learner.is_b_marked(step));
SASSERT(m_learner.m_pr.is_a_marked(step));
SASSERT(m_learner.m_pr.is_b_marked(step));
func_decl* d = step->get_decl();
symbol sym;
if(!m_learner.is_closed(step) && // if step is not already interpolated
step->get_decl_kind() == PR_TH_LEMMA && // and step is a Farkas lemma
d->get_num_parameters() >= 2 && // the Farkas coefficients are saved in the parameters of step
d->get_parameter(0).is_symbol(sym) && sym == "arith" && // the first two parameters are "arith", "farkas",
d->get_parameter(1).is_symbol(sym) && sym == "farkas" &&
d->get_num_parameters() >= m_learner.m.get_num_parents(step) + 2) // the following parameters are the Farkas coefficients
{
SASSERT(m_learner.m.has_fact(step));
is_farkas_lemma(m, step)) {
SASSERT(d->get_num_parameters() == m.get_num_parents(step) + 2);
SASSERT(m.has_fact(step));
vector<std::pair<app*,rational> > linear_combination; // collects all summands of the linear combination
coeff_lits_t linear_combination; // collects all summands of the linear combination
parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient
STRACE("spacer.farkas",
verbose_stream() << "Farkas input: "<< "\n";
for (unsigned i = 0; i < m_learner.m.get_num_parents(step); ++i)
{
SASSERT(m_learner.m.is_proof(step->get_arg(i)));
proof *prem = m.get_parent (step, i);
rational coef;
VERIFY(params[i].is_rational(coef));
bool b_pure = m_learner.is_b_pure (prem);
verbose_stream() << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m_learner.m.get_fact(prem), m_learner.m) << "\n";
}
);
verbose_stream() << "Farkas input: "<< "\n";
for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * prem = m.get_parent(step, i);
rational coef = params[i].get_rational();
bool b_pure = m_learner.m_pr.is_b_pure (prem);
verbose_stream() << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m.get_fact(prem), m_learner.m) << "\n";
}
);
bool can_be_closed = true;
for(unsigned i = 0; i < m_learner.m.get_num_parents(step); ++i)
{
SASSERT(m_learner.m.is_proof(step->get_arg(i)));
proof * premise = m.get_parent (step, i);
for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * premise = m.get_parent(step, i);
if (m_learner.is_b_marked(premise) && !m_learner.is_closed(premise))
if (m_learner.m_pr.is_b_marked(premise) && !m_learner.is_closed(premise))
{
SASSERT(!m_learner.is_a_marked(premise));
SASSERT(!m_learner.m_pr.is_a_marked(premise));
if (m_learner.only_contains_symbols_b(m_learner.m.get_fact(premise)) && !m_learner.is_h_marked(premise))
if (m_learner.m_pr.is_b_pure(premise))
{
rational coefficient;
VERIFY(params[i].is_rational(coefficient));
linear_combination.push_back(std::make_pair(to_app(m_learner.m.get_fact(premise)), abs(coefficient)));
rational coefficient = params[i].get_rational();
linear_combination.push_back
(std::make_pair(abs(coefficient), to_app(m.get_fact(premise))));
}
else
{
@ -357,99 +294,21 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
struct farkas_optimized_less_than_pairs
{
inline bool operator() (const std::pair<app*,rational>& pair1, const std::pair<app*,rational>& pair2) const
inline bool operator() (const std::pair<rational, app*>& pair1, const std::pair<rational, app*>& pair2) const
{
return (pair1.first->get_id() < pair2.first->get_id());
return (pair1.second->get_id() < pair2.second->get_id());
}
};
void unsat_core_plugin_farkas_lemma_optimized::finalize()
{
if(m_linear_combinations.empty())
if (m_linear_combinations.empty())
{
return;
}
DEBUG_CODE(
for (auto& linear_combination : m_linear_combinations) {
SASSERT(linear_combination.size() > 0);
});
// 1. construct ordered basis
ptr_vector<app> ordered_basis;
obj_map<app, unsigned> map;
unsigned counter = 0;
for (const auto& linear_combination : m_linear_combinations)
{
for (const auto& pair : linear_combination)
{
if (!map.contains(pair.first))
{
ordered_basis.push_back(pair.first);
map.insert(pair.first, counter++);
}
}
}
// 2. populate matrix
spacer_matrix matrix(m_linear_combinations.size(), ordered_basis.size());
for (unsigned i=0; i < m_linear_combinations.size(); ++i)
{
auto linear_combination = m_linear_combinations[i];
for (const auto& pair : linear_combination)
{
matrix.set(i, map[pair.first], pair.second);
}
}
// 3. perform gaussian elimination
unsigned i = matrix.perform_gaussian_elimination();
// 4. extract linear combinations from matrix and add result to core
for (unsigned k=0; k < i; k++)// i points to the row after the last row which is non-zero
{
ptr_vector<app> literals;
vector<rational> coefficients;
for (unsigned l=0; l < matrix.num_cols(); ++l)
{
if (!matrix.get(k,l).is_zero())
{
literals.push_back(ordered_basis[l]);
coefficients.push_back(matrix.get(k,l));
}
}
SASSERT(literals.size() > 0);
expr_ref linear_combination(m);
compute_linear_combination(coefficients, literals, linear_combination);
m_learner.add_lemma_to_core(linear_combination);
}
}
void unsat_core_plugin_farkas_lemma_optimized::compute_linear_combination(const vector<rational>& coefficients, const ptr_vector<app>& literals, expr_ref& res)
{
SASSERT(literals.size() == coefficients.size());
ast_manager& m = res.get_manager();
smt::farkas_util util(m);
for(unsigned i = 0; i < literals.size(); ++i)
{
util.add(coefficients[i], literals[i]);
}
expr_ref negated_linear_combination = util.get();
SASSERT(m.is_not(negated_linear_combination));
res = mk_not(m, negated_linear_combination); //TODO: rewrite the get-method to return nonnegated stuff?
}
void unsat_core_plugin_farkas_lemma_bounded::finalize() {
if (m_linear_combinations.empty()) {
return;
}
DEBUG_CODE(
for (auto& linear_combination : m_linear_combinations) {
SASSERT(linear_combination.size() > 0);
SASSERT(!linear_combination.empty());
});
// 1. construct ordered basis
@ -458,9 +317,72 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
unsigned counter = 0;
for (const auto& linear_combination : m_linear_combinations) {
for (const auto& pair : linear_combination) {
if (!map.contains(pair.first)) {
ordered_basis.push_back(pair.first);
map.insert(pair.first, counter++);
if (!map.contains(pair.second)) {
ordered_basis.push_back(pair.second);
map.insert(pair.second, counter++);
}
}
}
// 2. populate matrix
spacer_matrix matrix(m_linear_combinations.size(), ordered_basis.size());
for (unsigned i = 0; i < m_linear_combinations.size(); ++i) {
auto linear_combination = m_linear_combinations[i];
for (const auto& pair : linear_combination) {
matrix.set(i, map[pair.second], pair.first);
}
}
// 3. perform gaussian elimination
unsigned i = matrix.perform_gaussian_elimination();
// 4. extract linear combinations from matrix and add result to core
for (unsigned k = 0; k < i; ++k)// i points to the row after the last row which is non-zero
{
coeff_lits_t coeff_lits;
for (unsigned l = 0; l < matrix.num_cols(); ++l) {
if (!matrix.get(k,l).is_zero()) {
coeff_lits.push_back(std::make_pair(matrix.get(k, l), ordered_basis[l]));
}
}
SASSERT(!coeff_lits.empty());
expr_ref linear_combination = compute_linear_combination(coeff_lits);
m_learner.add_lemma_to_core(linear_combination);
}
}
expr_ref unsat_core_plugin_farkas_lemma_optimized::compute_linear_combination(const coeff_lits_t& coeff_lits) {
smt::farkas_util util(m);
for (auto const & p : coeff_lits) {
util.add(p.first, p.second);
}
expr_ref negated_linear_combination = util.get();
SASSERT(m.is_not(negated_linear_combination));
return expr_ref(mk_not(m, negated_linear_combination), m);
//TODO: rewrite the get-method to return nonnegated stuff?
}
void unsat_core_plugin_farkas_lemma_bounded::finalize() {
if (m_linear_combinations.empty()) {
return;
}
DEBUG_CODE(
for (auto& linear_combination : m_linear_combinations) {
SASSERT(!linear_combination.empty());
});
// 1. construct ordered basis
ptr_vector<app> ordered_basis;
obj_map<app, unsigned> map;
unsigned counter = 0;
for (const auto& linear_combination : m_linear_combinations) {
for (const auto& pair : linear_combination) {
if (!map.contains(pair.second)) {
ordered_basis.push_back(pair.second);
map.insert(pair.second, counter++);
}
}
}
@ -471,7 +393,7 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
for (unsigned i=0; i < m_linear_combinations.size(); ++i) {
auto linear_combination = m_linear_combinations[i];
for (const auto& pair : linear_combination) {
matrix.set(i, map[pair.first], pair.second);
matrix.set(i, map[pair.second], pair.first);
}
}
matrix.print_matrix();
@ -483,13 +405,12 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
arith_util util(m);
vector<expr_ref_vector> coeffs;
for (unsigned i=0; i < matrix.num_rows(); ++i) {
for (unsigned i = 0; i < matrix.num_rows(); ++i) {
coeffs.push_back(expr_ref_vector(m));
}
vector<expr_ref_vector> bounded_vectors;
for (unsigned j=0; j < matrix.num_cols(); ++j)
{
for (unsigned j = 0; j < matrix.num_cols(); ++j) {
bounded_vectors.push_back(expr_ref_vector(m));
}
@ -498,87 +419,67 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
{
params_ref p;
p.set_bool("model", true);
scoped_ptr<solver> s = mk_smt_solver(m, p, symbol::null); // TODO: incremental version?
solver_ref s = mk_smt_solver(m, p, symbol::null); // TODO: incremental version?
// add new variables w_in,
for (unsigned i=0; i < matrix.num_rows(); ++i)
{
for (unsigned i = 0; i < matrix.num_rows(); ++i) {
std::string name = "w_" + std::to_string(i) + std::to_string(n);
func_decl_ref decl(m);
decl = m.mk_func_decl(symbol(name.c_str()), 0, (sort*const*)nullptr, util.mk_int());
coeffs[i].push_back(m.mk_const(decl));
coeffs[i].push_back(m.mk_const(name, util.mk_int()));
}
// we need s_jn
for (unsigned j=0; j < matrix.num_cols(); ++j)
{
for (unsigned j = 0; j < matrix.num_cols(); ++j) {
std::string name = "s_" + std::to_string(j) + std::to_string(n);
func_decl_ref decl(m);
decl = m.mk_func_decl(symbol(name.c_str()), 0, (sort*const*)nullptr, util.mk_int());
expr_ref s_jn(m);
s_jn = m.mk_const(decl);
bounded_vectors[j].push_back(s_jn);
bounded_vectors[j].push_back(m.mk_const(name, util.mk_int()));
}
// assert bounds for all s_jn
for (unsigned l=0; l < n; ++l) {
for (unsigned j=0; j < matrix.num_cols(); ++j) {
for (unsigned l = 0; l < n; ++l) {
for (unsigned j = 0; j < matrix.num_cols(); ++j) {
expr* s_jn = bounded_vectors[j][l].get();
expr_ref lb(util.mk_le(util.mk_int(0), s_jn), m);
expr_ref ub(util.mk_le(s_jn, util.mk_int(1)), m);
s->assert_expr(lb);
s->assert_expr(ub);
}
}
// assert: forall i,j: a_ij = sum_k w_ik * s_jk
for (unsigned i=0; i < matrix.num_rows(); ++i)
{
for (unsigned j=0; j < matrix.num_cols(); ++j)
{
for (unsigned i = 0; i < matrix.num_rows(); ++i) {
for (unsigned j = 0; j < matrix.num_cols(); ++j) {
SASSERT(matrix.get(i, j).is_int());
app_ref a_ij(util.mk_numeral(matrix.get(i,j), true),m);
app_ref sum(m);
sum = util.mk_int(0);
for (unsigned k=0; k < n; ++k)
{
app_ref a_ij(util.mk_numeral(matrix.get(i,j), true), m);
app_ref sum(util.mk_int(0), m);
for (unsigned k = 0; k < n; ++k) {
sum = util.mk_add(sum, util.mk_mul(coeffs[i][k].get(), bounded_vectors[j][k].get()));
}
expr_ref eq(m.mk_eq(a_ij, sum),m);
s->assert_expr(eq);
}
expr_ref eq(m.mk_eq(a_ij, sum), m);
s->assert_expr(eq);
}
}
// check result
lbool res = s->check_sat(0,nullptr);
lbool res = s->check_sat(0, nullptr);
// if sat extract model and add corresponding linear combinations to core
if (res == lbool::l_true) {
model_ref model;
s->get_model(model);
for (unsigned k=0; k < n; ++k) {
ptr_vector<app> literals;
vector<rational> coefficients;
for (unsigned j=0; j < matrix.num_cols(); ++j) {
for (unsigned k = 0; k < n; ++k) {
coeff_lits_t coeff_lits;
for (unsigned j = 0; j < matrix.num_cols(); ++j) {
expr_ref evaluation(m);
model.get()->eval(bounded_vectors[j][k].get(), evaluation, false);
if (!util.is_zero(evaluation)) {
literals.push_back(ordered_basis[j]);
coefficients.push_back(rational(1));
coeff_lits.push_back(std::make_pair(rational(1), ordered_basis[j]));
}
}
SASSERT(!literals.empty()); // since then previous outer loop would have found solution already
expr_ref linear_combination(m);
compute_linear_combination(coefficients, literals, linear_combination);
SASSERT(!coeff_lits.empty()); // since then previous outer loop would have found solution already
expr_ref linear_combination = compute_linear_combination(coeff_lits);
m_learner.add_lemma_to_core(linear_combination);
}
return;
@ -586,7 +487,7 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
}
}
unsat_core_plugin_min_cut::unsat_core_plugin_min_cut(unsat_core_learner& learner, ast_manager& m) : unsat_core_plugin(learner), m(m){}
unsat_core_plugin_min_cut::unsat_core_plugin_min_cut(unsat_core_learner& learner, ast_manager& m) : unsat_core_plugin(learner) {}
/*
* traverses proof rooted in step and constructs graph, which corresponds to the proof-DAG, with the following differences:
@ -603,8 +504,8 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
{
ptr_vector<proof> todo;
SASSERT(m_learner.is_a_marked(step));
SASSERT(m_learner.is_b_marked(step));
SASSERT(m_learner.m_pr.is_a_marked(step));
SASSERT(m_learner.m_pr.is_b_marked(step));
SASSERT(m.get_num_parents(step) > 0);
SASSERT(!m_learner.is_closed(step));
todo.push_back(step);
@ -621,7 +522,7 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
// add an edge from current to each leaf of that subproof
// add the leaves to todo
advance_to_lowest_partial_cut(current, todo);
m_visited.mark(current, true);
}
@ -629,22 +530,16 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
m_learner.set_closed(step, true);
}
void unsat_core_plugin_min_cut::advance_to_lowest_partial_cut(proof* step, ptr_vector<proof>& todo)
{
bool is_sink = true;
ast_manager &m = m_learner.m;
ptr_vector<proof> todo_subproof;
ptr_buffer<proof> todo_subproof;
for (unsigned i = 0, sz = m.get_num_parents(step); i < sz; ++i)
{
proof* premise = m.get_parent (step, i);
{
if (m_learner.is_b_marked(premise))
{
todo_subproof.push_back(premise);
}
for (proof* premise : m.get_parents(step)) {
if (m_learner.m_pr.is_b_marked(premise)) {
todo_subproof.push_back(premise);
}
}
while (!todo_subproof.empty())
@ -655,19 +550,19 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
// if we need to deal with the node
if (!m_learner.is_closed(current))
{
SASSERT(!m_learner.is_a_marked(current)); // by I.H. the step must be already visited
SASSERT(!m_learner.m_pr.is_a_marked(current)); // by I.H. the step must be already visited
// and the current step needs to be interpolated:
if (m_learner.is_b_marked(current))
if (m_learner.m_pr.is_b_marked(current))
{
// if we trust the current step and we are able to use it
if (m_learner.is_b_pure (current) &&
if (m_learner.m_pr.is_b_pure (current) &&
(m.is_asserted(current) ||
is_literal(m, m.get_fact(current))))
{
// we found a leaf of the subproof, so
// 1) we add corresponding edges
if (m_learner.is_a_marked(step))
if (m_learner.m_pr.is_a_marked(step))
{
add_edge(nullptr, current); // current is sink
}
@ -682,10 +577,7 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
// otherwise continue search for leaves of subproof
else
{
for (unsigned i = 0; i < m_learner.m.get_num_parents(current); ++i)
{
SASSERT(m_learner.m.is_proof(current->get_arg(i)));
proof* premise = m.get_parent (current, i);
for (proof* premise : m.get_parents(current)) {
todo_subproof.push_back(premise);
}
}
@ -707,6 +599,8 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
*/
void unsat_core_plugin_min_cut::add_edge(proof* i, proof* j)
{
SASSERT(i != nullptr || j != nullptr);
unsigned node_i;
unsigned node_j;
if (i == nullptr)
@ -735,7 +629,7 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
m_node_to_formula[node_other] = m.get_fact(i);
m_node_to_formula[node_i] = m.get_fact(i);
m_min_cut.add_edge(node_other, node_i);
m_min_cut.add_edge(node_other, node_i, 1);
}
}
@ -765,26 +659,32 @@ void unsat_core_plugin_farkas_lemma::compute_linear_combination(const vector<rat
m_node_to_formula[node_j] = m.get_fact(j);
m_node_to_formula[node_other] = m.get_fact(j);
m_min_cut.add_edge(node_j, node_other);
m_min_cut.add_edge(node_j, node_other, 1);
}
}
// finally connect nodes
m_min_cut.add_edge(node_i, node_j);
// finally connect nodes (if there is not already a connection i -> j (only relevant if i is the supersource))
if (!(i == nullptr && m_connected_to_s.is_marked(j)))
{
m_min_cut.add_edge(node_i, node_j, 1);
}
if (i == nullptr)
{
m_connected_to_s.mark(j, true);
}
}
/*
* computes min-cut on the graph constructed by compute_partial_core-method
* and adds the corresponding lemmas to the core
*/
void unsat_core_plugin_min_cut::finalize()
{
void unsat_core_plugin_min_cut::finalize() {
unsigned_vector cut_nodes;
m_min_cut.compute_min_cut(cut_nodes);
for (unsigned cut_node : cut_nodes)
{
for (unsigned cut_node : cut_nodes) {
m_learner.add_lemma_to_core(m_node_to_formula[cut_node]);
}
}
}
}
}

104
src/muz/spacer/spacer_unsat_core_plugin.h
View file

@ -23,84 +23,73 @@ Revision History:
namespace spacer {
class unsat_core_learner;
class unsat_core_learner;
class unsat_core_plugin {
public:
unsat_core_plugin(unsat_core_learner& learner) : m_learner(learner){};
virtual ~unsat_core_plugin(){};
virtual void compute_partial_core(proof* step) = 0;
virtual void finalize(){};
unsat_core_learner& m_learner;
};
class unsat_core_plugin_lemma : public unsat_core_plugin {
public:
unsat_core_plugin_lemma(unsat_core_learner& learner) : unsat_core_plugin(learner){};
void compute_partial_core(proof* step) override;
private:
void add_lowest_split_to_core(proof* step) const;
};
class unsat_core_plugin_farkas_lemma : public unsat_core_plugin {
public:
unsat_core_plugin_farkas_lemma(unsat_core_learner& learner, bool split_literals, bool use_constant_from_a=true) : unsat_core_plugin(learner), m_split_literals(split_literals), m_use_constant_from_a(use_constant_from_a) {};
void compute_partial_core(proof* step) override;
private:
bool m_split_literals;
bool m_use_constant_from_a;
/*
* compute linear combination of literals 'literals' having coefficients 'coefficients' and save result in res
*/
void compute_linear_combination(const vector<rational>& coefficients, const ptr_vector<app>& literals, expr_ref& res);
};
class unsat_core_plugin_farkas_lemma_optimized : public unsat_core_plugin {
public:
unsat_core_plugin_farkas_lemma_optimized(unsat_core_learner& learner, ast_manager& m) : unsat_core_plugin(learner), m(m) {};
void compute_partial_core(proof* step) override;
void finalize() override;
class unsat_core_plugin {
protected:
vector<vector<std::pair<app*, rational> > > m_linear_combinations;
typedef vector<std::pair<rational, app*>> coeff_lits_t;
ast_manager& m;
public:
unsat_core_plugin(unsat_core_learner& learner);
virtual ~unsat_core_plugin() {};
virtual void compute_partial_core(proof* step) = 0;
virtual void finalize(){};
unsat_core_learner& m_learner;
};
class unsat_core_plugin_lemma : public unsat_core_plugin {
public:
unsat_core_plugin_lemma(unsat_core_learner& learner) : unsat_core_plugin(learner){};
void compute_partial_core(proof* step) override;
private:
void add_lowest_split_to_core(proof* step) const;
};
class unsat_core_plugin_farkas_lemma : public unsat_core_plugin {
public:
unsat_core_plugin_farkas_lemma(unsat_core_learner& learner,
bool split_literals,
bool use_constant_from_a=true) :
unsat_core_plugin(learner),
m_split_literals(split_literals),
m_use_constant_from_a(use_constant_from_a) {};
void compute_partial_core(proof* step) override;
private:
bool m_split_literals;
bool m_use_constant_from_a;
/*
* compute linear combination of literals 'literals' having coefficients 'coefficients' and save result in res
*/
void compute_linear_combination(const vector<rational>& coefficients, const ptr_vector<app>& literals, expr_ref& res);
expr_ref compute_linear_combination(const coeff_lits_t& coeff_lits);
};
class unsat_core_plugin_farkas_lemma_optimized : public unsat_core_plugin {
public:
unsat_core_plugin_farkas_lemma_optimized(unsat_core_learner& learner, ast_manager& m) : unsat_core_plugin(learner) {};
void compute_partial_core(proof* step) override;
void finalize() override;
protected:
vector<coeff_lits_t> m_linear_combinations;
/*
* compute linear combination of literals 'literals' having coefficients 'coefficients' and save result in res
*/
expr_ref compute_linear_combination(const coeff_lits_t& coeff_lits);
};
class unsat_core_plugin_farkas_lemma_bounded : public unsat_core_plugin_farkas_lemma_optimized {
public:
unsat_core_plugin_farkas_lemma_bounded(unsat_core_learner& learner, ast_manager& m) : unsat_core_plugin_farkas_lemma_optimized(learner, m) {};
void finalize() override;
};
class unsat_core_plugin_min_cut : public unsat_core_plugin {
public:
unsat_core_plugin_min_cut(unsat_core_learner& learner, ast_manager& m);
void compute_partial_core(proof* step) override;
void finalize() override;
private:
ast_manager& m;
ast_mark m_visited; // saves for each node i whether the subproof with root i has already been added to the min-cut-problem
obj_map<proof, unsigned> m_proof_to_node_minus; // maps proof-steps to the corresponding minus-nodes (the ones which are closer to source)
obj_map<proof, unsigned> m_proof_to_node_plus; // maps proof-steps to the corresponding plus-nodes (the ones which are closer to sink)
@ -108,6 +97,7 @@ private:
void add_edge(proof* i, proof* j);
vector<expr*> m_node_to_formula; // maps each node to the corresponding formula in the original proof
ast_mark m_connected_to_s; // remember which nodes have already been connected to the supersource, in order to avoid multiple edges.
min_cut m_min_cut;
};

1268
src/muz/spacer/spacer_util.cpp
View file

File diff suppressed because it is too large Load diff

215
src/muz/spacer/spacer_util.h
View file

@ -44,129 +44,120 @@ class model_evaluator;
namespace spacer {
inline unsigned infty_level () {return UINT_MAX;}
inline bool is_infty_level(unsigned lvl)
{ return lvl == infty_level (); }
inline unsigned next_level(unsigned lvl)
{ return is_infty_level(lvl)?lvl:(lvl+1); }
inline unsigned prev_level (unsigned lvl)
{
if(is_infty_level(lvl)) { return infty_level(); }
if(lvl == 0) { return 0; }
return lvl -1;
}
struct pp_level {
unsigned m_level;
pp_level(unsigned l): m_level(l) {}
};
inline std::ostream& operator<<(std::ostream& out, pp_level const& p)
{
if (is_infty_level(p.m_level)) {
return out << "oo";
} else {
return out << p.m_level;
inline unsigned infty_level () {
return UINT_MAX;
}
}
inline bool is_infty_level(unsigned lvl) {
return lvl == infty_level ();
}
inline unsigned next_level(unsigned lvl) {
return is_infty_level(lvl)?lvl:(lvl+1);
}
inline unsigned prev_level (unsigned lvl) {
if (is_infty_level(lvl)) return infty_level();
if (lvl == 0) return 0;
return lvl - 1;
}
typedef ptr_vector<app> app_vector;
typedef ptr_vector<func_decl> decl_vector;
typedef obj_hashtable<func_decl> func_decl_set;
struct pp_level {
unsigned m_level;
pp_level(unsigned l): m_level(l) {}
};
inline std::ostream& operator<<(std::ostream& out, pp_level const& p) {
if (is_infty_level(p.m_level)) {
return out << "oo";
} else {
return out << p.m_level;
}
}
class model_evaluator_util {
ast_manager& m;
model_ref m_model;
model_evaluator* m_mev;
typedef ptr_vector<app> app_vector;
typedef ptr_vector<func_decl> decl_vector;
typedef obj_hashtable<func_decl> func_decl_set;
// TBD: deprecate
class model_evaluator_util {
ast_manager& m;
model_ref m_model;
model_evaluator* m_mev;
/// initialize with a given model. All previous state is lost. model can be NULL
void reset (model *model);
public:
model_evaluator_util(ast_manager& m);
~model_evaluator_util();
void set_model(model &model) {reset (&model);}
model_ref &get_model() {return m_model;}
ast_manager& get_ast_manager() const {return m;}
public:
bool is_true (const expr_ref_vector &v);
bool is_false(expr* x);
bool is_true(expr* x);
bool eval (const expr_ref_vector &v, expr_ref &result, bool model_completion);
/// evaluates an expression
bool eval (expr *e, expr_ref &result, bool model_completion);
// expr_ref eval(expr* e, bool complete=true);
};
/// initialize with a given model. All previous state is lost. model can be NULL
void reset (model *model);
public:
model_evaluator_util(ast_manager& m);
~model_evaluator_util();
/**
\brief hoist non-boolean if expressions.
*/
void to_mbp_benchmark(std::ostream &out, const expr* fml, const app_ref_vector &vars);
void set_model(model &model) {reset (&model);}
model_ref &get_model() {return m_model;}
ast_manager& get_ast_manager() const {return m;}
// TBD: deprecate by qe::mbp
/**
* do the following in sequence
* 1. use qe_lite to cheaply eliminate vars
* 2. for remaining boolean vars, substitute using M
* 3. use MBP for remaining array and arith variables
* 4. for any remaining arith variables, substitute using M
*/
void qe_project (ast_manager& m, app_ref_vector& vars, expr_ref& fml,
const model_ref& M, bool reduce_all_selects=false, bool native_mbp=false,
bool dont_sub=false);
public:
bool is_true (const expr_ref_vector &v);
bool is_false(expr* x);
bool is_true(expr* x);
bool eval (const expr_ref_vector &v, expr_ref &result, bool model_completion);
/// evaluates an expression
bool eval (expr *e, expr_ref &result, bool model_completion);
// expr_ref eval(expr* e, bool complete=true);
};
/**
\brief replace variables that are used in many disequalities by
an equality using the model.
Assumption: the model satisfies the conjunctions.
*/
void reduce_disequalities(model& model, unsigned threshold, expr_ref& fml);
/**
\brief hoist non-boolean if expressions.
*/
void hoist_non_bool_if(expr_ref& fml);
bool is_difference_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls);
bool is_utvpi_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls);
/**
* do the following in sequence
* 1. use qe_lite to cheaply eliminate vars
* 2. for remaining boolean vars, substitute using M
* 3. use MBP for remaining array and arith variables
* 4. for any remaining arith variables, substitute using M
*/
void qe_project (ast_manager& m, app_ref_vector& vars, expr_ref& fml,
const model_ref& M, bool reduce_all_selects=false, bool native_mbp=false,
bool dont_sub=false);
void qe_project (ast_manager& m, app_ref_vector& vars, expr_ref& fml, model_ref& M, expr_map& map);
void expand_literals(ast_manager &m, expr_ref_vector& conjs);
void compute_implicant_literals (model_evaluator_util &mev,
expr_ref_vector &formula, expr_ref_vector &res);
void simplify_bounds (expr_ref_vector &lemmas);
void normalize(expr *e, expr_ref &out, bool use_simplify_bounds = true, bool factor_eqs = false);
/** ground expression by replacing all free variables by skolem constants */
void ground_expr (expr *e, expr_ref &out, app_ref_vector &vars);
void mbqi_project (model &M, app_ref_vector &vars, expr_ref &fml);
bool contains_selects (expr* fml, ast_manager& m);
void get_select_indices (expr* fml, app_ref_vector& indices, ast_manager& m);
void find_decls (expr* fml, app_ref_vector& decls, std::string& prefix);
/** extended pretty-printer
* used for debugging
* disables aliasing of common sub-expressions
*/
struct mk_epp : public mk_pp {
params_ref m_epp_params;
expr_ref m_epp_expr;
void qe_project (ast_manager& m, app_ref_vector& vars, expr_ref& fml, model_ref& M, expr_map& map);
// TBD: sort out
void expand_literals(ast_manager &m, expr_ref_vector& conjs);
void compute_implicant_literals (model_evaluator_util &mev, expr_ref_vector &formula, expr_ref_vector &res);
void simplify_bounds (expr_ref_vector &lemmas);
void normalize(expr *e, expr_ref &out, bool use_simplify_bounds = true, bool factor_eqs = false);
/**
* Ground expression by replacing all free variables by skolem
* constants. On return, out is the resulting expression, and vars is
* a map from variable ids to corresponding skolem constants.
*/
void ground_expr (expr *e, expr_ref &out, app_ref_vector &vars);
void mbqi_project (model &M, app_ref_vector &vars, expr_ref &fml);
bool contains_selects (expr* fml, ast_manager& m);
void get_select_indices (expr* fml, app_ref_vector& indices, ast_manager& m);
void find_decls (expr* fml, app_ref_vector& decls, std::string& prefix);
/**
* extended pretty-printer
* used for debugging
* disables aliasing of common sub-expressions
*/
struct mk_epp : public mk_pp {
params_ref m_epp_params;
expr_ref m_epp_expr;
mk_epp(ast *t, ast_manager &m, unsigned indent = 0, unsigned num_vars = 0, char const * var_prefix = nullptr);
void rw(expr *e, expr_ref &out);
};
void rw(expr *e, expr_ref &out);
};
}
#endif

354
src/muz/spacer/spacer_virtual_solver.cpp
View file

@ -1,354 +0,0 @@
/**
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_virtual_solver.cpp
Abstract:
multi-solver view of a single smt::kernel
Author:
Arie Gurfinkel
Notes:
--*/
#include "muz/spacer/spacer_virtual_solver.h"
#include "ast/ast_util.h"
#include "ast/ast_pp_util.h"
#include "muz/spacer/spacer_util.h"
#include "ast/rewriter/bool_rewriter.h"
#include "ast/proofs/proof_checker.h"
#include "ast/proofs/proof_utils.h"
#include "ast/scoped_proof.h"
namespace spacer {
virtual_solver::virtual_solver(virtual_solver_factory &factory,
smt::kernel &context, app* pred) :
solver_na2as(context.m()),
m_factory(factory),
m(context.m()),
m_context(context),
m_pred(pred, m),
m_virtual(!m.is_true(pred)),
m_assertions(m),
m_head(0),
m_flat(m),
m_pushed(false),
m_in_delay_scope(false),
m_dump_benchmarks(factory.fparams().m_dump_benchmarks),
m_dump_counter(0),
m_proof(m)
{
// -- insert m_pred->true background assumption this will not
// -- change m_context, but will add m_pred to
// -- the private field solver_na2as::m_assumptions
if (m_virtual)
{ solver_na2as::assert_expr_core2(m.mk_true(), m_pred); }
}
virtual_solver::~virtual_solver()
{
SASSERT(!m_pushed || get_scope_level() > 0);
if (m_pushed) { pop(get_scope_level()); }
if (m_virtual) {
m_pred = m.mk_not(m_pred);
m_context.assert_expr(m_pred);
}
}
namespace {
// TBD: move to ast/proofs/elim_aux_assertions
}
proof *virtual_solver::get_proof()
{
scoped_watch _t_(m_factory.m_proof_watch);
if (!m_proof.get()) {
elim_aux_assertions pc(m_pred);
m_proof = m_context.get_proof();
pc(m, m_proof.get(), m_proof);
}
return m_proof.get();
}
bool virtual_solver::is_aux_predicate(expr *p)
{return is_app(p) && to_app(p) == m_pred.get();}
lbool virtual_solver::check_sat_core(unsigned num_assumptions,
expr *const * assumptions)
{
SASSERT(!m_pushed || get_scope_level() > 0);
m_proof.reset();
scoped_watch _t_(m_factory.m_check_watch);
m_factory.m_stats.m_num_smt_checks++;
stopwatch sw;
sw.start();
internalize_assertions();
if (false) {
std::stringstream file_name;
file_name << "virt_solver";
if (m_virtual) { file_name << "_" << m_pred->get_decl()->get_name(); }
file_name << "_" << (m_dump_counter++) << ".smt2";
verbose_stream() << "Dumping SMT2 benchmark: " << file_name.str() << "\n";
std::ofstream out(file_name.str().c_str());
to_smt2_benchmark(out, m_context, num_assumptions, assumptions,
"virt_solver");
out << "(exit)\n";
out.close();
}
lbool res = m_context.check(num_assumptions, assumptions);
sw.stop();
if (res == l_true) {
m_factory.m_check_sat_watch.add(sw);
m_factory.m_stats.m_num_sat_smt_checks++;
} else if (res == l_undef) {
m_factory.m_check_undef_watch.add(sw);
m_factory.m_stats.m_num_undef_smt_checks++;
}
set_status(res);
if (m_dump_benchmarks &&
sw.get_seconds() >= m_factory.fparams().m_dump_min_time) {
std::stringstream file_name;
file_name << "virt_solver";
if (m_virtual) { file_name << "_" << m_pred->get_decl()->get_name(); }
file_name << "_" << (m_dump_counter++) << ".smt2";
std::ofstream out(file_name.str().c_str());
out << "(set-info :status ";
if (res == l_true) { out << "sat"; }
else if (res == l_false) { out << "unsat"; }
else { out << "unknown"; }
out << ")\n";
to_smt2_benchmark(out, m_context, num_assumptions, assumptions,
"virt_solver");
out << "(exit)\n";
::statistics st;
m_context.collect_statistics(st);
st.update("time", sw.get_seconds());
st.display_smt2(out);
out.close();
if (m_factory.fparams().m_dump_recheck) {
scoped_no_proof _no_proof_(m);
smt_params p;
stopwatch sw2;
smt::kernel kernel(m, p);
for (unsigned i = 0, sz = m_context.size(); i < sz; ++i)
{ kernel.assert_expr(m_context.get_formula(i)); }
sw2.start();
kernel.check(num_assumptions, assumptions);
sw2.stop();
verbose_stream() << file_name.str() << " :orig "
<< sw.get_seconds() << " :new " << sw2.get_seconds();
}
}
return res;
}
void virtual_solver::push_core()
{
SASSERT(!m_pushed || get_scope_level() > 0);
if (m_in_delay_scope) {
// second push
internalize_assertions();
m_context.push();
m_pushed = true;
m_in_delay_scope = false;
}
if (!m_pushed) { m_in_delay_scope = true; }
else {
SASSERT(m_pushed);
SASSERT(!m_in_delay_scope);
m_context.push();
}
}
void virtual_solver::pop_core(unsigned n) {
SASSERT(!m_pushed || get_scope_level() > 0);
if (m_pushed) {
SASSERT(!m_in_delay_scope);
m_context.pop(n);
m_pushed = get_scope_level() - n > 0;
}
else {
m_in_delay_scope = get_scope_level() - n > 0;
}
}
void virtual_solver::get_unsat_core(ptr_vector<expr> &r)
{
for (unsigned i = 0, sz = m_context.get_unsat_core_size(); i < sz; ++i) {
expr *core = m_context.get_unsat_core_expr(i);
if (is_aux_predicate(core)) { continue; }
r.push_back(core);
}
}
void virtual_solver::assert_expr_core(expr *e)
{
SASSERT(!m_pushed || get_scope_level() > 0);
if (m.is_true(e)) { return; }
if (m_in_delay_scope) {
internalize_assertions();
m_context.push();
m_pushed = true;
m_in_delay_scope = false;
}
if (m_pushed)
{ m_context.assert_expr(e); }
else {
m_flat.push_back(e);
flatten_and(m_flat);
m_assertions.append(m_flat);
m_flat.reset();
}
}
void virtual_solver::internalize_assertions()
{
SASSERT(!m_pushed || m_head == m_assertions.size());
for (unsigned sz = m_assertions.size(); m_head < sz; ++m_head) {
expr_ref f(m);
f = m.mk_implies(m_pred, (m_assertions.get(m_head)));
m_context.assert_expr(f);
}
}
void virtual_solver::refresh()
{
SASSERT(!m_pushed);
m_head = 0;
}
void virtual_solver::reset()
{
SASSERT(!m_pushed);
m_head = 0;
m_assertions.reset();
m_factory.refresh();
}
void virtual_solver::get_labels(svector<symbol> &r)
{
r.reset();
buffer<symbol> tmp;
m_context.get_relevant_labels(nullptr, tmp);
r.append(tmp.size(), tmp.c_ptr());
}
solver* virtual_solver::translate(ast_manager& m, params_ref const& p)
{
UNREACHABLE();
return nullptr;
}
void virtual_solver::updt_params(params_ref const &p) { m_factory.updt_params(p); }
void virtual_solver::collect_param_descrs(param_descrs &r) { m_factory.collect_param_descrs(r); }
void virtual_solver::set_produce_models(bool f) { m_factory.set_produce_models(f); }
smt_params &virtual_solver::fparams() {return m_factory.fparams();}
void virtual_solver::to_smt2_benchmark(std::ostream &out,
smt::kernel &context,
unsigned num_assumptions,
expr * const * assumptions,
char const * name,
symbol const &logic,
char const * status,
char const * attributes)
{
ast_pp_util pp(m);
expr_ref_vector asserts(m);
for (unsigned i = 0, sz = context.size(); i < sz; ++i) {
asserts.push_back(context.get_formula(i));
pp.collect(asserts.back());
}
pp.collect(num_assumptions, assumptions);
pp.display_decls(out);
pp.display_asserts(out, asserts);
out << "(check-sat ";
for (unsigned i = 0; i < num_assumptions; ++i)
{ out << mk_pp(assumptions[i], m) << " "; }
out << ")\n";
}
virtual_solver_factory::virtual_solver_factory(ast_manager &mgr, smt_params &fparams) :
m_fparams(fparams), m(mgr), m_context(m, m_fparams)
{
m_stats.reset();
}
virtual_solver* virtual_solver_factory::mk_solver()
{
std::stringstream name;
name << "vsolver#" << m_solvers.size();
app_ref pred(m);
pred = m.mk_const(symbol(name.str().c_str()), m.mk_bool_sort());
SASSERT(m_context.get_scope_level() == 0);
m_solvers.push_back(alloc(virtual_solver, *this, m_context, pred));
return m_solvers.back();
}
void virtual_solver_factory::collect_statistics(statistics &st) const
{
m_context.collect_statistics(st);
st.update("time.virtual_solver.smt.total", m_check_watch.get_seconds());
st.update("time.virtual_solver.smt.total.sat", m_check_sat_watch.get_seconds());
st.update("time.virtual_solver.smt.total.undef", m_check_undef_watch.get_seconds());
st.update("time.virtual_solver.proof", m_proof_watch.get_seconds());
st.update("virtual_solver.checks", m_stats.m_num_smt_checks);
st.update("virtual_solver.checks.sat", m_stats.m_num_sat_smt_checks);
st.update("virtual_solver.checks.undef", m_stats.m_num_undef_smt_checks);
}
void virtual_solver_factory::reset_statistics()
{
m_context.reset_statistics();
m_stats.reset();
m_check_sat_watch.reset();
m_check_undef_watch.reset();
m_check_watch.reset();
m_proof_watch.reset();
}
void virtual_solver_factory::refresh()
{
m_context.reset();
for (unsigned i = 0, e = m_solvers.size(); i < e; ++i)
{ m_solvers [i]->refresh(); }
}
virtual_solver_factory::~virtual_solver_factory()
{
for (unsigned i = 0, e = m_solvers.size(); i < e; ++i)
{ dealloc(m_solvers [i]); }
}
}

154
src/muz/spacer/spacer_virtual_solver.h
View file

@ -1,154 +0,0 @@
/**
Copyright (c) 2017 Arie Gurfinkel
Module Name:
spacer_virtual_solver.h
Abstract:
multi-solver view of a single smt::kernel
Author:
Arie Gurfinkel
Notes:
--*/
#ifndef SPACER_VIRTUAL_SOLVER_H_
#define SPACER_VIRTUAL_SOLVER_H_
#include"ast/ast.h"
#include"util/params.h"
#include"solver/solver_na2as.h"
#include"smt/smt_kernel.h"
#include"smt/params/smt_params.h"
#include"util/stopwatch.h"
namespace spacer {
class virtual_solver_factory;
class virtual_solver : public solver_na2as {
friend class virtual_solver_factory;
private:
virtual_solver_factory &m_factory;
ast_manager &m;
smt::kernel &m_context;
app_ref m_pred;
bool m_virtual;
expr_ref_vector m_assertions;
unsigned m_head;
// temporary to flatten conjunction
expr_ref_vector m_flat;
bool m_pushed;
bool m_in_delay_scope;
bool m_dump_benchmarks;
unsigned m_dump_counter;
proof_ref m_proof;
virtual_solver(virtual_solver_factory &factory, smt::kernel &context, app* pred);
bool is_aux_predicate(expr *p);
void internalize_assertions();
void to_smt2_benchmark(std::ostream &out,
smt::kernel &context,
unsigned num_assumptions,
expr * const * assumptions,
char const * name = "benchmarks",
symbol const &logic = symbol::null,
char const * status = "unknown",
char const * attributes = "");
void refresh();
public:
~virtual_solver() override;
unsigned get_num_assumptions() const override
{
unsigned sz = solver_na2as::get_num_assumptions();
return m_virtual ? sz - 1 : sz;
}
expr* get_assumption(unsigned idx) const override
{
if(m_virtual) { idx++; }
return solver_na2as::get_assumption(idx);
}
void get_unsat_core(ptr_vector<expr> &r) override;
void assert_expr_core(expr *e) override;
void collect_statistics(statistics &st) const override {}
void get_model_core(model_ref &m) override {m_context.get_model(m);}
proof* get_proof() override;
std::string reason_unknown() const override
{return m_context.last_failure_as_string();}
void set_reason_unknown(char const *msg) override
{m_context.set_reason_unknown(msg);}
ast_manager& get_manager() const override {return m;}
void get_labels(svector<symbol> &r) override;
void set_produce_models(bool f) override;
smt_params &fparams();
void reset();
expr_ref_vector cube(expr_ref_vector&, unsigned) override { return expr_ref_vector(m); }
void set_progress_callback(progress_callback *callback) override {UNREACHABLE();}
solver *translate(ast_manager &m, params_ref const &p) override;
void updt_params(params_ref const &p) override;
void collect_param_descrs(param_descrs &r) override;
protected:
lbool check_sat_core(unsigned num_assumptions, expr *const * assumptions) override;
void push_core() override;
void pop_core(unsigned n) override;
};
/// multi-solver abstraction on top of a single smt::kernel
class virtual_solver_factory {
friend class virtual_solver;
private:
smt_params &m_fparams;
ast_manager &m;
smt::kernel m_context;
/// solvers managed by this factory
ptr_vector<virtual_solver> m_solvers;
struct stats {
unsigned m_num_smt_checks;
unsigned m_num_sat_smt_checks;
unsigned m_num_undef_smt_checks;
stats() { reset(); }
void reset() { memset(this, 0, sizeof(*this)); }
};
stats m_stats;
stopwatch m_check_watch;
stopwatch m_check_sat_watch;
stopwatch m_check_undef_watch;
stopwatch m_proof_watch;
void refresh();
smt_params &fparams() { return m_fparams; }
public:
virtual_solver_factory(ast_manager &mgr, smt_params &fparams);
virtual ~virtual_solver_factory();
virtual_solver* mk_solver();
void collect_statistics(statistics &st) const;
void reset_statistics();
void updt_params(params_ref const &p) { m_fparams.updt_params(p); }
void collect_param_descrs(param_descrs &r) { /* empty */ }
void set_produce_models(bool f) { m_fparams.m_model = f; }
bool get_produce_models() { return m_fparams.m_model; }
};
}
#endif

2
src/muz/tab/tab_context.cpp
View file

@ -30,7 +30,7 @@ Revision History:
#include "ast/for_each_expr.h"
#include "ast/substitution/matcher.h"
#include "ast/scoped_proof.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include "ast/ast_util.h"
namespace tb {

2
src/muz/transforms/dl_mk_array_blast.cpp
View file

@ -42,7 +42,7 @@ namespace datalog {
}
bool mk_array_blast::is_store_def(expr* e, expr*& x, expr*& y) {
if (m.is_iff(e, x, y) || m.is_eq(e, x, y)) {
if (m.is_eq(e, x, y)) {
if (!a.is_store(y)) {
std::swap(x,y);
}

2
src/muz/transforms/dl_mk_array_eq_rewrite.cpp
View file

@ -20,7 +20,7 @@ Revision History:
#include "ast/expr_abstract.h"
#include "muz/base/dl_context.h"
#include "muz/base/dl_context.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include "muz/transforms/dl_mk_array_eq_rewrite.h"
#include "ast/factor_equivs.h"

2
src/muz/transforms/dl_mk_array_instantiation.cpp
View file

@ -23,7 +23,7 @@ Revision History:
#include "muz/base/dl_context.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/expr_abstract.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
namespace datalog {

52
src/muz/transforms/dl_mk_bit_blast.cpp
View file

@ -24,7 +24,7 @@ Revision History:
#include "ast/rewriter/expr_safe_replace.h"
#include "tactic/generic_model_converter.h"
#include "muz/transforms/dl_mk_interp_tail_simplifier.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include "ast/scoped_proof.h"
#include "model/model_v2_pp.h"
@ -32,9 +32,9 @@ namespace datalog {
//
// P(v) :- Q(extract[1:1]v ++ 0), R(1 ++ extract[0:0]v).
// ->
// ->
// P(bv(x,y)) :- Q(bv(x,0)), R(bv(1,y)) .
//
//
// Introduce P_bv:
// P_bv(x,y) :- Q_bv(x,0), R_bv(1,y)
// P(bv(x,y)) :- P_bv(x,y)
@ -51,7 +51,7 @@ namespace datalog {
bit_blast_model_converter(ast_manager& m):
m(m),
m_bv(m),
m_old_funcs(m),
m_old_funcs(m),
m_new_funcs(m) {}
void insert(func_decl* old_f, func_decl* new_f) {
@ -73,7 +73,7 @@ namespace datalog {
func_decl* q = m_old_funcs[i].get();
func_interp* f = model->get_func_interp(p);
if (!f) continue;
expr_ref body(m);
expr_ref body(m);
unsigned arity_q = q->get_arity();
TRACE("dl",
model_v2_pp(tout, *model);
@ -87,10 +87,10 @@ namespace datalog {
if (f) {
body = f->get_interp();
SASSERT(!f->is_partial());
SASSERT(body);
SASSERT(body);
}
else {
body = m.mk_false();
body = m.mk_false();
}
unsigned idx = 0;
expr_ref arg(m), proj(m);
@ -104,18 +104,18 @@ namespace datalog {
for (unsigned k = 0; k < sz; ++k) {
parameter p(k);
proj = m.mk_app(m_bv.get_family_id(), OP_BIT2BOOL, 1, &p, 1, &t);
sub.insert(m.mk_var(idx++, m.mk_bool_sort()), proj);
sub.insert(m.mk_var(idx++, m.mk_bool_sort()), proj);
}
}
else {
sub.insert(m.mk_var(idx++, s), arg);
}
}
sub(body);
sub(body);
g->set_else(body);
model->register_decl(q, g);
}
}
}
}
};
class expand_mkbv_cfg : public default_rewriter_cfg {
@ -134,10 +134,10 @@ namespace datalog {
public:
expand_mkbv_cfg(context& ctx):
m_context(ctx),
m_context(ctx),
m(ctx.get_manager()),
m_util(m),
m_args(m),
m_args(m),
m_f_vars(m),
m_g_vars(m),
m_old_funcs(m),
@ -152,8 +152,8 @@ namespace datalog {
void set_dst(rule_set* dst) { m_dst = dst; }
func_decl_ref_vector const& old_funcs() const { return m_old_funcs; }
func_decl_ref_vector const& new_funcs() const { return m_new_funcs; }
br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result, proof_ref & result_pr) {
br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result, proof_ref & result_pr) {
if (num == 0) {
if (m_src->is_output_predicate(f))
m_dst->set_output_predicate(f);
@ -165,9 +165,9 @@ namespace datalog {
return BR_FAILED;
}
//
//
// f(mk_bv(args),...)
//
//
m_args.reset();
m_g_vars.reset();
m_f_vars.reset();
@ -191,9 +191,9 @@ namespace datalog {
}
}
func_decl* g = nullptr;
if (!m_pred2blast.find(f, g)) {
ptr_vector<sort> domain;
for (unsigned i = 0; i < m_args.size(); ++i) {
domain.push_back(m.get_sort(m_args[i].get()));
@ -262,7 +262,7 @@ namespace datalog {
m_params.set_bool("blast_quant", true);
m_blaster.updt_params(m_params);
}
rule_set * operator()(rule_set const & source) {
// TODO pc
if (!m_context.xform_bit_blast()) {
@ -270,8 +270,8 @@ namespace datalog {
}
rule_manager& rm = m_context.get_rule_manager();
unsigned sz = source.get_num_rules();
expr_ref fml(m);
rule_set * result = alloc(rule_set, m_context);
expr_ref fml(m);
rule_set * result = alloc(rule_set, m_context);
m_rewriter.m_cfg.set_src(&source);
m_rewriter.m_cfg.set_dst(result);
for (unsigned i = 0; !m_context.canceled() && i < sz; ++i) {
@ -299,8 +299,8 @@ namespace datalog {
if (!source.contains(*I))
result->set_output_predicate(*I);
}
if (m_context.get_model_converter()) {
if (m_context.get_model_converter()) {
generic_model_converter* fmc = alloc(generic_model_converter, m, "dl_mk_bit_blast");
bit_blast_model_converter* bvmc = alloc(bit_blast_model_converter, m);
func_decl_ref_vector const& old_funcs = m_rewriter.m_cfg.old_funcs();
@ -311,7 +311,7 @@ namespace datalog {
}
m_context.add_model_converter(concat(bvmc, fmc));
}
return result;
}
};
@ -326,6 +326,6 @@ namespace datalog {
rule_set * mk_bit_blast::operator()(rule_set const & source) {
return (*m_impl)(source);
}
}
};

31
src/muz/transforms/dl_mk_interp_tail_simplifier.cpp
View file

@ -27,7 +27,7 @@ Revision History:
#include "muz/transforms/dl_mk_interp_tail_simplifier.h"
#include "ast/ast_util.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
namespace datalog {
// -----------------------------------
@ -46,7 +46,7 @@ namespace datalog {
bool mk_interp_tail_simplifier::rule_substitution::unify(expr * e1, expr * e2) {
SASSERT(m_rule);
//we need to apply the current substitution in order to ensure the unifier
//we need to apply the current substitution in order to ensure the unifier
//works in an incremental way
expr_ref e1_s(m);
expr_ref e2_s(m);
@ -268,7 +268,7 @@ namespace datalog {
if (neq) {
have_pair = false;
v[prev_pair_idx] = neq;
read_idx++;
continue;
}
@ -294,7 +294,7 @@ namespace datalog {
//bool detect_same_variable_conj_pairs
br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result,
br_status reduce_app(func_decl * f, unsigned num, expr * const * args, expr_ref & result,
proof_ref & result_pr)
{
if (m.is_not(f) && (m.is_and(args[0]) || m.is_or(args[0]))) {
@ -307,15 +307,15 @@ namespace datalog {
m_app_args.push_back(tmp);
}
if (m.is_and(args[0])) {
result = mk_or(m_app_args);
result = mk_or(m_app_args);
}
else {
result = mk_and(m_app_args);
result = mk_and(m_app_args);
}
return BR_REWRITE2;
}
if (!m.is_and(f) && !m.is_or(f)) {
return BR_FAILED;
if (!m.is_and(f) && !m.is_or(f)) {
return BR_FAILED;
}
if (num == 0) {
if (m.is_and(f)) {
@ -375,7 +375,7 @@ namespace datalog {
m_simp(ctx.get_rewriter()),
a(m),
m_rule_subst(ctx),
m_tail(m),
m_tail(m),
m_itail_members(m),
m_conj(m) {
m_cfg = alloc(normalizer_cfg, m);
@ -386,7 +386,7 @@ namespace datalog {
dealloc(m_rw);
dealloc(m_cfg);
}
void mk_interp_tail_simplifier::simplify_expr(app * a, expr_ref& res)
{
@ -537,7 +537,7 @@ namespace datalog {
simplify_expr(itail.get(), simp_res);
modified |= itail.get() != simp_res.get();
if (m.is_false(simp_res)) {
TRACE("dl", r->display(m_context, tout << "rule is infeasible\n"););
return false;
@ -568,7 +568,7 @@ namespace datalog {
rule_ref pro_var_eq_result(m_context.get_rule_manager());
if (propagate_variable_equivalences(res, pro_var_eq_result)) {
SASSERT(rule_counter().get_max_rule_var(*r.get())==0 ||
SASSERT(rule_counter().get_max_rule_var(*r.get())==0 ||
rule_counter().get_max_rule_var(*r.get()) > rule_counter().get_max_rule_var(*pro_var_eq_result.get()));
r = pro_var_eq_result;
goto start;
@ -607,8 +607,8 @@ namespace datalog {
rule_set * res = alloc(rule_set, m_context);
if (transform_rules(source, *res)) {
res->inherit_predicates(source);
TRACE("dl",
source.display(tout);
TRACE("dl",
source.display(tout);
res->display(tout););
} else {
dealloc(res);
@ -616,6 +616,5 @@ namespace datalog {
}
return res;
}
};
};

49
src/muz/transforms/dl_mk_quantifier_abstraction.cpp
View file

@ -11,7 +11,7 @@ Abstract:
Author:
Ken McMillan
Ken McMillan
Andrey Rybalchenko
Nikolaj Bjorner (nbjorner) 2013-04-02
@ -23,13 +23,12 @@ Revision History:
#include "muz/base/dl_context.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/expr_abstract.h"
#include "muz/base/fixedpoint_params.hpp"
namespace datalog {
// model converter:
// model converter:
// Given model for P^(x, y, i, a[i])
// create model: P(x,y,a) == forall i . P^(x,y,i,a[i])
// requires substitution and list of bound variables.
@ -55,7 +54,7 @@ namespace datalog {
void display(std::ostream& out) override { display_add(out, m); }
void get_units(obj_map<expr, bool>& units) override { units.reset(); }
void get_units(obj_map<expr, bool>& units) override { units.reset(); }
void insert(func_decl* old_p, func_decl* new_p, expr_ref_vector& sub, sort_ref_vector& sorts, svector<bool> const& bound) {
m_old_funcs.push_back(old_p);
@ -74,7 +73,7 @@ namespace datalog {
sort_ref_vector const& sorts = m_sorts[i];
svector<bool> const& is_bound = m_bound[i];
func_interp* f = old_model->get_func_interp(p);
expr_ref body(m);
expr_ref body(m);
unsigned arity_q = q->get_arity();
SASSERT(0 < p->get_arity());
func_interp* g = alloc(func_interp, m, arity_q);
@ -82,7 +81,7 @@ namespace datalog {
if (f) {
body = f->get_interp();
SASSERT(!f->is_partial());
SASSERT(body);
SASSERT(body);
}
else {
expr_ref_vector args(m);
@ -94,7 +93,7 @@ namespace datalog {
// Create quantifier wrapper around body.
TRACE("dl", tout << mk_pp(body, m) << "\n";);
// 1. replace variables by the compound terms from
// 1. replace variables by the compound terms from
// the original predicate.
expr_safe_replace rep(m);
for (unsigned i = 0; i < sub.size(); ++i) {
@ -121,7 +120,7 @@ namespace datalog {
_free.push_back(consts.back());
}
}
rep(body);
rep(body);
rep.reset();
TRACE("dl", tout << mk_pp(body, m) << "\n";);
@ -130,18 +129,18 @@ namespace datalog {
body = m.mk_forall(names.size(), bound_sorts.c_ptr(), names.c_ptr(), body);
TRACE("dl", tout << mk_pp(body, m) << "\n";);
// 4. replace remaining constants by variables.
// 4. replace remaining constants by variables.
for (unsigned i = 0; i < _free.size(); ++i) {
rep.insert(_free[i].get(), m.mk_var(i, m.get_sort(_free[i].get())));
}
rep(body);
rep(body);
g->set_else(body);
TRACE("dl", tout << mk_pp(body, m) << "\n";);
new_model->register_decl(q, g);
}
}
old_model = new_model;
}
}
};
mk_quantifier_abstraction::mk_quantifier_abstraction(
@ -154,7 +153,7 @@ namespace datalog {
m_mc(nullptr) {
}
mk_quantifier_abstraction::~mk_quantifier_abstraction() {
mk_quantifier_abstraction::~mk_quantifier_abstraction() {
}
func_decl* mk_quantifier_abstraction::declare_pred(rule_set const& rules, rule_set& dst, func_decl* old_p) {
@ -178,7 +177,7 @@ namespace datalog {
func_decl* new_p = nullptr;
if (!m_old2new.find(old_p, new_p)) {
expr_ref_vector sub(m), vars(m);
svector<bool> bound;
svector<bool> bound;
sort_ref_vector domain(m), sorts(m);
expr_ref arg(m);
for (unsigned i = 0; i < sz; ++i) {
@ -208,7 +207,7 @@ namespace datalog {
bound.push_back(false);
sub.push_back(arg);
sorts.push_back(s0);
}
}
SASSERT(old_p->get_range() == m.mk_bool_sort());
new_p = m.mk_func_decl(old_p->get_name(), domain.size(), domain.c_ptr(), old_p->get_range());
m_refs.push_back(new_p);
@ -242,12 +241,12 @@ namespace datalog {
}
args.push_back(arg);
}
TRACE("dl",
TRACE("dl",
tout << mk_pp(new_p, m) << "\n";
for (unsigned i = 0; i < args.size(); ++i) {
tout << mk_pp(args[i].get(), m) << "\n";
});
return app_ref(m.mk_app(new_p, args.size(), args.c_ptr()), m);
return app_ref(m.mk_app(new_p, args.size(), args.c_ptr()), m);
}
app_ref mk_quantifier_abstraction::mk_tail(rule_set const& rules, rule_set& dst, app* p) {
@ -272,7 +271,7 @@ namespace datalog {
for (unsigned i = 0; i < sz; ++i) {
arg = ps->get_arg(i);
sort* s = m.get_sort(arg);
bool is_pattern = false;
bool is_pattern = false;
while (a.is_array(s)) {
is_pattern = true;
unsigned arity = get_array_arity(s);
@ -304,9 +303,9 @@ namespace datalog {
ptr_vector<expr> args2;
args2.push_back(arg);
args2.append(num_args, args);
return a.mk_select(args2.size(), args2.c_ptr());
return a.mk_select(args2.size(), args2.c_ptr());
}
rule_set * mk_quantifier_abstraction::operator()(rule_set const & source) {
if (!m_ctx.quantify_arrays()) {
return nullptr;
@ -334,10 +333,10 @@ namespace datalog {
}
rule_set * result = alloc(rule_set, m_ctx);
for (unsigned i = 0; i < sz; ++i) {
for (unsigned i = 0; i < sz; ++i) {
tail.reset();
rule & r = *source.get_rule(i);
TRACE("dl", r.display(m_ctx, tout); );
TRACE("dl", r.display(m_ctx, tout); );
unsigned cnt = vc.get_max_rule_var(r)+1;
unsigned utsz = r.get_uninterpreted_tail_size();
unsigned tsz = r.get_tail_size();
@ -352,8 +351,8 @@ namespace datalog {
proof_ref pr(m);
rm.mk_rule(fml, pr, *result, r.name());
TRACE("dl", result->last()->display(m_ctx, tout););
}
}
// proof converter: proofs are not necessarily preserved using this transformation.
if (m_old2new.empty()) {
@ -371,5 +370,3 @@ namespace datalog {
};

2
src/muz/transforms/dl_mk_quantifier_instantiation.cpp
View file

@ -180,7 +180,7 @@ namespace datalog {
}
m_terms[n] = e;
visited.mark(e);
if (m.is_eq(e, e1, e2) || m.is_iff(e, e1, e2)) {
if (m.is_eq(e, e1, e2)) {
m_uf.merge(e1->get_id(), e2->get_id());
}
if (is_app(e)) {

129
src/muz/transforms/dl_mk_rule_inliner.cpp
View file

@ -18,7 +18,7 @@ Revision History:
Added linear_inline 2012-9-10 (nbjorner)
Disable inliner for quantified rules 2012-10-31 (nbjorner)
Notes:
Resolution transformation (resolve):
@ -27,7 +27,7 @@ Resolution transformation (resolve):
--------------------------------------------------
P(x) :- R(z), phi(x,y), psi(y,z)
Proof converter:
Proof converter:
replace assumption (*) by rule and upper assumptions.
@ -37,9 +37,9 @@ Subsumption transformation (remove rule):
P(x) :- Q(y), phi(x,y) Rules
---------------------------------
Rules
Model converter:
Model converter:
P(x) := P(x) or (exists y . Q(y) & phi(x,y))
@ -52,7 +52,7 @@ Subsumption transformation (remove rule):
#include "ast/rewriter/rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "muz/transforms/dl_mk_rule_inliner.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
namespace datalog {
@ -67,15 +67,15 @@ namespace datalog {
unsigned var_cnt = std::max(vc.get_max_rule_var(tgt), vc.get_max_rule_var(src))+1;
m_subst.reset();
m_subst.reserve(2, var_cnt);
m_ready = m_unif(tgt.get_tail(tgt_idx), src.get_head(), m_subst);
if (m_ready) {
m_deltas[0] = 0;
m_deltas[1] = var_cnt;
TRACE("dl",
output_predicate(m_context, src.get_head(), tout << "unify rules ");
output_predicate(m_context, tgt.get_head(), tout << "\n");
TRACE("dl",
output_predicate(m_context, src.get_head(), tout << "unify rules ");
output_predicate(m_context, tgt.get_head(), tout << "\n");
tout << "\n";);
}
return m_ready;
@ -90,7 +90,7 @@ namespace datalog {
}
void rule_unifier::apply(
rule const& r, bool is_tgt, unsigned skipped_index,
rule const& r, bool is_tgt, unsigned skipped_index,
app_ref_vector& res, svector<bool>& res_neg) {
unsigned rule_len = r.get_tail_size();
for (unsigned i = 0; i < rule_len; i++) {
@ -127,7 +127,7 @@ namespace datalog {
);
if (m_normalize) {
m_rm.fix_unbound_vars(res, true);
m_rm.fix_unbound_vars(res, true);
if (m_interp_simplifier.transform_rule(res.get(), simpl_rule)) {
res = simpl_rule;
return true;
@ -150,8 +150,8 @@ namespace datalog {
for (unsigned i = 0; i < sorts.size(); ++i) {
v = m.mk_var(i, sorts[i]);
m_subst.apply(2, m_deltas, expr_offset(v, is_tgt?0:1), w);
result.push_back(w);
}
result.push_back(w);
}
return result;
}
@ -184,7 +184,7 @@ namespace datalog {
expr_ref_vector s2 = m_unifier.get_rule_subst(src, false);
datalog::resolve_rule(m_rm, tgt, src, tail_index, s1, s2, *res.get());
}
return true;
return true;
}
else {
TRACE("dl", res->display(m_context, tout << "interpreted tail is unsat\n"););
@ -240,12 +240,12 @@ namespace datalog {
return false;
}
//
// these conditions are optional, they avoid possible exponential increase
//
// these conditions are optional, they avoid possible exponential increase
// in the size of the problem
//
//
return
return
//m_head_pred_non_empty_tails_ctr.get(pred)<=1
m_head_pred_ctr.get(pred) <= 1
|| (m_tail_pred_ctr.get(pred) <= 1 && m_head_pred_ctr.get(pred) <= 4)
@ -253,7 +253,7 @@ namespace datalog {
}
/** Caller has to dealloc the returned object */
rule_set * mk_rule_inliner::create_allowed_rule_set(rule_set const & orig)
rule_set * mk_rule_inliner::create_allowed_rule_set(rule_set const & orig)
{
rule_set * res = alloc(rule_set, m_context);
for (rule * r : orig) {
@ -268,7 +268,7 @@ namespace datalog {
/**
Try to make the set of inlined predicates acyclic by forbidding inlining of one
predicate from each strongly connected component. Return true if we did forbide some
predicate from each strongly connected component. Return true if we did forbide some
predicate, and false if the set of rules is already acyclic.
*/
bool mk_rule_inliner::forbid_preds_from_cycles(rule_set const & r)
@ -276,7 +276,7 @@ namespace datalog {
SASSERT(r.is_closed());
bool something_forbidden = false;
const rule_stratifier::comp_vector& comps = r.get_stratifier().get_strats();
for (rule_stratifier::item_set * stratum : comps) {
@ -293,12 +293,12 @@ namespace datalog {
return something_forbidden;
}
bool mk_rule_inliner::forbid_multiple_multipliers(const rule_set & orig,
bool mk_rule_inliner::forbid_multiple_multipliers(const rule_set & orig,
rule_set const & proposed_inlined_rules) {
bool something_forbidden = false;
const rule_stratifier::comp_vector& comps =
const rule_stratifier::comp_vector& comps =
proposed_inlined_rules.get_stratifier().get_strats();
for (rule_stratifier::item_set * stratum : comps) {
@ -332,7 +332,7 @@ namespace datalog {
}
else {
is_multi_head_pred = true;
m_head_pred_ctr.get(head_pred) =
m_head_pred_ctr.get(head_pred) =
m_head_pred_ctr.get(head_pred)*tail_pred_head_cnt;
}
}
@ -379,7 +379,7 @@ namespace datalog {
void mk_rule_inliner::plan_inlining(rule_set const & orig)
{
count_pred_occurrences(orig);
scoped_ptr<rule_set> candidate_inlined_set = create_allowed_rule_set(orig);
while (forbid_preds_from_cycles(*candidate_inlined_set)) {
candidate_inlined_set = create_allowed_rule_set(orig);
@ -458,8 +458,8 @@ namespace datalog {
rule_ref r(rl, m_rm);
func_decl * pred = r->get_decl();
// if inlining is allowed, then we are eliminating
// this relation through inlining,
// if inlining is allowed, then we are eliminating
// this relation through inlining,
// so we don't add its rules to the result
something_done |= !inlining_allowed(orig, pred) && transform_rule(orig, r, tgt);
@ -472,14 +472,14 @@ namespace datalog {
}
}
}
return something_done;
}
/**
Check whether rule r is oriented in a particular ordering.
This is to avoid infinite cycle of inlining in the eager inliner.
Out ordering is lexicographic, comparing atoms first on stratum they are in,
then on arity and then on ast ID of their func_decl.
*/
@ -488,7 +488,7 @@ namespace datalog {
unsigned head_strat = strat.get_predicate_strat(head_pred);
unsigned head_arity = head_pred->get_arity();
unsigned pt_len = r->get_positive_tail_size();
for (unsigned ti=0; ti < pt_len; ++ti) {
for (unsigned ti=0; ti < pt_len; ++ti) {
func_decl * pred = r->get_decl(ti);
unsigned pred_strat = strat.get_predicate_strat(pred);
SASSERT(pred_strat <= head_strat);
@ -516,7 +516,7 @@ namespace datalog {
unsigned pt_len = r->get_positive_tail_size();
for (unsigned ti = 0; ti < pt_len; ++ti) {
func_decl * pred = r->get_decl(ti);
if (pred == head_pred || m_preds_with_facts.contains(pred)) { continue; }
@ -532,7 +532,7 @@ namespace datalog {
}
else {
inlining_candidate = nullptr;
for (unsigned ri = 0; ri < rule_cnt; ++ri) {
rule * pred_rule = pred_rules[ri];
if (!m_unifier.unify_rules(*r, ti, *pred_rule)) {
@ -540,9 +540,9 @@ namespace datalog {
continue;
}
if (inlining_candidate != nullptr) {
// We have two rules that can be inlined into the current
// We have two rules that can be inlined into the current
// tail predicate. In this situation we don't do inlinning
// on this tail atom, as we don't want the overall number
// on this tail atom, as we don't want the overall number
// of rules to increase.
goto process_next_tail;
}
@ -608,14 +608,14 @@ namespace datalog {
P(1,x) :- P(1,z), phi(x,y), psi(y,z)
whenever P(0,x) is not unifiable with the
whenever P(0,x) is not unifiable with the
body of the rule where it appears (P(1,z))
and P(0,x) is unifiable with at most one (?)
and P(0,x) is unifiable with at most one (?)
other rule (and it does not occur negatively).
*/
bool mk_rule_inliner::visitor::operator()(expr* e) {
m_unifiers.append(m_positions.find(e));
TRACE("dl",
TRACE("dl",
tout << "unifier: " << (m_unifiers.empty()?0:m_unifiers.back());
tout << " num unifiers: " << m_unifiers.size();
tout << " num positions: " << m_positions.find(e).size() << "\n";
@ -640,7 +640,7 @@ namespace datalog {
}
unsigned_vector const& mk_rule_inliner::visitor::del_position(expr* e, unsigned j) {
obj_map<expr, unsigned_vector>::obj_map_entry * et = m_positions.find_core(e);
obj_map<expr, unsigned_vector>::obj_map_entry * et = m_positions.find_core(e);
SASSERT(et && et->get_data().m_value.contains(j));
et->get_data().m_value.erase(j);
return et->get_data().m_value;
@ -654,7 +654,7 @@ namespace datalog {
m_head_visitor.add_position(head, i);
m_head_index.insert(head);
m_pinned.push_back(r);
if (source.is_output_predicate(headd) ||
m_preds_with_facts.contains(headd)) {
can_remove.set(i, false);
@ -667,10 +667,10 @@ namespace datalog {
m_tail_visitor.add_position(tail, i);
m_tail_index.insert(tail);
}
bool can_exp =
bool can_exp =
tl_sz == 1
&& r->get_positive_tail_size() == 1
&& !m_preds_with_facts.contains(r->get_decl(0))
&& r->get_positive_tail_size() == 1
&& !m_preds_with_facts.contains(r->get_decl(0))
&& !source.is_output_predicate(r->get_decl(0));
can_expand.set(i, can_exp);
}
@ -682,14 +682,14 @@ namespace datalog {
for (unsigned j = 0; j < tl_sz; ++j) {
app* tail = r->get_tail(j);
m_tail_visitor.del_position(tail, i);
}
}
}
#define PRT(_x_) ((_x_)?"T":"F")
bool mk_rule_inliner::inline_linear(scoped_ptr<rule_set>& rules) {
bool done_something = false;
bool done_something = false;
unsigned sz = rules->get_num_rules();
m_head_visitor.reset(sz);
@ -704,7 +704,7 @@ namespace datalog {
acc.push_back(rules->get_rule(i));
}
// set up unification index.
// set up unification index.
svector<bool>& can_remove = m_head_visitor.can_remove();
svector<bool>& can_expand = m_head_visitor.can_expand();
@ -729,7 +729,7 @@ namespace datalog {
svector<bool> valid;
valid.reset();
valid.resize(sz, true);
valid.resize(sz, true);
bool allow_branching = m_context.get_params().xform_inline_linear_branch();
@ -738,9 +738,9 @@ namespace datalog {
while (true) {
rule_ref r(acc[i].get(), m_rm);
TRACE("dl", r->display(m_context, tout << "processing: " << i << "\n"););
if (!valid.get(i)) {
TRACE("dl", tout << "invalid: " << i << "\n";);
break;
@ -762,9 +762,9 @@ namespace datalog {
TRACE("dl", tout << PRT(can_remove.get(j)) << " " << PRT(valid.get(j)) << " " << PRT(i != j) << "\n";);
break;
}
rule* r2 = acc[j].get();
// check that the head of r2 only unifies with this single body position.
TRACE("dl", output_predicate(m_context, r2->get_head(), tout << "unify head: "); tout << "\n";);
m_tail_visitor.reset();
@ -776,7 +776,7 @@ namespace datalog {
TRACE("dl", tout << "too many tails " << num_tail_unifiers << "\n";);
break;
}
rule_ref rl_res(m_rm);
if (!try_to_inline_rule(*r.get(), *r2, 0, rl_res)) {
TRACE("dl", r->display(m_context, tout << "inlining failed\n"); r2->display(m_context, tout); );
@ -787,12 +787,12 @@ namespace datalog {
del_rule(r, i);
add_rule(*rules, rl_res.get(), i);
r = rl_res;
acc[i] = r.get();
can_expand.set(i, can_expand.get(j));
if (num_tail_unifiers == 1) {
TRACE("dl", tout << "setting invalid: " << j << "\n";);
valid.set(j, false);
@ -815,22 +815,22 @@ namespace datalog {
res->inherit_predicates(*rules);
TRACE("dl", res->display(tout););
rules = res.detach();
}
}
return done_something;
}
rule_set * mk_rule_inliner::operator()(rule_set const & source) {
bool something_done = false;
ref<horn_subsume_model_converter> hsmc;
ref<horn_subsume_model_converter> hsmc;
if (source.get_num_rules() == 0) {
return nullptr;
}
for (rule const* r : source)
if (has_quantifier(*r))
return nullptr;
for (rule const* r : source)
if (has_quantifier(*r))
return nullptr;
if (m_context.get_model_converter()) {
hsmc = alloc(horn_subsume_model_converter, m);
@ -841,15 +841,15 @@ namespace datalog {
if (m_context.get_params().xform_inline_eager()) {
TRACE("dl", source.display(tout << "before eager inlining\n"););
plan_inlining(source);
something_done = transform_rules(source, *res);
plan_inlining(source);
something_done = transform_rules(source, *res);
VERIFY(res->close()); //this transformation doesn't break the negation stratification
// try eager inlining
if (do_eager_inlining(res)) {
something_done = true;
}
}
TRACE("dl", res->display(tout << "after eager inlining\n"););
}
}
if (something_done) {
res->inherit_predicates(source);
}
@ -870,6 +870,5 @@ namespace datalog {
return res.detach();
}
};
};

20
src/muz/transforms/dl_mk_scale.cpp
View file

@ -18,7 +18,7 @@ Revision History:
#include "muz/transforms/dl_mk_scale.h"
#include "muz/base/dl_context.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
namespace datalog {
@ -37,7 +37,7 @@ namespace datalog {
m_trail.push_back(new_f);
m_new2old.insert(new_f, old_f);
}
void get_units(obj_map<expr, bool>& units) override { units.reset(); }
void operator()(model_ref& md) override {
@ -74,7 +74,7 @@ namespace datalog {
old_model->register_decl(old_p, old_fi);
}
}
// register values that have not been scaled.
unsigned sz = md->get_num_constants();
for (unsigned i = 0; i < sz; ++i) {
@ -111,12 +111,12 @@ namespace datalog {
m_ctx(ctx),
a(m),
m_trail(m),
m_eqs(m) {
m_eqs(m) {
}
mk_scale::~mk_scale() {
mk_scale::~mk_scale() {
}
rule_set * mk_scale::operator()(rule_set const & source) {
if (!m_ctx.scale()) {
return nullptr;
@ -135,7 +135,7 @@ namespace datalog {
}
m_mc = smc.get();
for (unsigned i = 0; i < sz; ++i) {
for (unsigned i = 0; i < sz; ++i) {
rule & r = *source.get_rule(i);
unsigned utsz = r.get_uninterpreted_tail_size();
unsigned tsz = r.get_tail_size();
@ -157,10 +157,10 @@ namespace datalog {
tail.push_back(a.mk_gt(m.mk_var(num_vars, a.mk_real()), a.mk_numeral(rational(0), false)));
neg.resize(tail.size(), false);
new_rule = rm.mk(new_pred, tail.size(), tail.c_ptr(), neg.c_ptr(), r.name(), true);
result->add_rule(new_rule);
result->add_rule(new_rule);
if (source.is_output_predicate(r.get_decl())) {
result->set_output_predicate(new_rule->get_decl());
}
}
}
TRACE("dl", result->display(tout););
if (m_mc) {
@ -227,7 +227,7 @@ namespace datalog {
a.is_lt(e) || a.is_gt(e)) {
expr_ref_vector args(m);
for (unsigned i = 0; i < ap->get_num_args(); ++i) {
args.push_back(linearize(sigma_idx, ap->get_arg(i)));
args.push_back(linearize(sigma_idx, ap->get_arg(i)));
}
result = m.mk_app(ap->get_decl(), args.size(), args.c_ptr());
}

25
src/muz/transforms/dl_mk_subsumption_checker.cpp
View file

@ -24,7 +24,7 @@ Revision History:
#include "ast/rewriter/rewriter.h"
#include "ast/rewriter/rewriter_def.h"
#include "muz/transforms/dl_mk_subsumption_checker.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
#include "tactic/generic_model_converter.h"
@ -39,8 +39,8 @@ namespace datalog {
bool mk_subsumption_checker::is_total_rule(const rule * r) {
if (r->get_tail_size() != 0) {
return false;
if (r->get_tail_size() != 0) {
return false;
}
unsigned pt_len = r->get_positive_tail_size();
@ -113,7 +113,7 @@ namespace datalog {
}
bool mk_subsumption_checker::transform_rule(rule * r,
bool mk_subsumption_checker::transform_rule(rule * r,
rule_subsumption_index& subs_index, rule_ref & res)
{
unsigned u_len = r->get_uninterpreted_tail_size();
@ -133,7 +133,7 @@ namespace datalog {
if(m_total_relations.contains(tail_atom->get_decl())
|| subs_index.is_subsumed(tail_atom)) {
if(neg) {
//rule contains negated total relation, this means that it is unsatisfiable
//rule contains negated total relation, this means that it is unsatisfiable
//and can be removed
return false;
}
@ -143,8 +143,8 @@ namespace datalog {
}
}
if(!neg && head.get()==tail_atom) {
//rule contains its head positively in the tail, therefore
//it will never add any new facts to the relation, so it
//rule contains its head positively in the tail, therefore
//it will never add any new facts to the relation, so it
//can be removed
return false;
}
@ -197,9 +197,9 @@ namespace datalog {
if (m_total_relations.contains(head_pred)) {
if (!orig.is_output_predicate(head_pred) ||
total_relations_with_included_rules.contains(head_pred)) {
//We just skip definitions of total non-output relations as
//We just skip definitions of total non-output relations as
//we'll eliminate them from the problem.
//We also skip rules of total output relations for which we have
//We also skip rules of total output relations for which we have
//already output the rule which implies their totality.
modified = true;
continue;
@ -286,7 +286,7 @@ namespace datalog {
obj_hashtable<app> * head_store;
if(m_ground_unconditional_rule_heads.find(pred, head_store)) {
//Some relations may receive facts by ground unconditioned rules.
//We scanned for those earlier, so now we check whether we cannot get a
//We scanned for those earlier, so now we check whether we cannot get a
//better estimate of relation size from these.
unsigned gnd_rule_cnt = head_store->size();
@ -334,7 +334,7 @@ namespace datalog {
rule_set * mk_subsumption_checker::operator()(rule_set const & source) {
// TODO mc
if (!m_context.get_params ().xform_subsumption_checker())
if (!m_context.get_params ().xform_subsumption_checker())
return nullptr;
m_have_new_total_rule = false;
@ -366,6 +366,5 @@ namespace datalog {
return res;
}
};
};

4
src/muz/transforms/dl_transforms.cpp
View file

@ -35,7 +35,7 @@ Revision History:
#include "muz/transforms/dl_mk_scale.h"
#include "muz/transforms/dl_mk_array_eq_rewrite.h"
#include "muz/transforms/dl_mk_array_instantiation.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/base/fp_params.hpp"
namespace datalog {
@ -72,7 +72,7 @@ namespace datalog {
transf.register_plugin(alloc(datalog::mk_rule_inliner, ctx, 34970));
transf.register_plugin(alloc(datalog::mk_coi_filter, ctx, 34960));
transf.register_plugin(alloc(datalog::mk_interp_tail_simplifier, ctx, 34950));
if (ctx.get_params().datalog_subsumption()) {
transf.register_plugin(alloc(datalog::mk_subsumption_checker, ctx, 34940));
transf.register_plugin(alloc(datalog::mk_rule_inliner, ctx, 34930));