mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-27 02:45:51 +00:00
Code Activity

enable proof production with difference logic, integrate with PDR engine

Browse source 
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2012-10-20 04:25:58 -07:00
parent 28a4f51ea5
commit 2e73957f97
10 changed files with 500 additions and 385 deletions
Download patch file Download diff file Expand all files Collapse all files

60
lib/pdr_context.cpp
View file

@ -55,8 +55,8 @@ namespace pdr {
// ----------------
// pred_tansformer
pred_transformer::pred_transformer(manager& pm, func_decl* head):
pm(pm), m(pm.get_manager()), m_head(head, m),
pred_transformer::pred_transformer(context& ctx, manager& pm, func_decl* head):
ctx(ctx), pm(pm), m(pm.get_manager()), m_head(head, m),
m_sig(m), m_solver(pm, head->get_name()),
m_invariants(m), m_transition(m), m_initial_state(m),
m_reachable(pm, pm.get_params()) {}
@ -464,6 +464,10 @@ namespace pdr {
th_rewriter rw(m);
rw(m_transition);
rw(m_initial_state);
if (ctx.is_dl()) {
hoist_non_bool_if(m_transition);
hoist_non_bool_if(m_initial_state);
}
m_solver.add_formula(m_transition);
m_solver.add_level_formula(m_initial_state, 0);
TRACE("pdr",
@ -1072,7 +1076,8 @@ namespace pdr {
m_search(m_params.get_bool(":bfs-model-search", true)),
m_last_result(l_undef),
m_inductive_lvl(0),
m_cancel(false)
m_cancel(false),
m_is_dl(false)
{
}
@ -1104,7 +1109,7 @@ namespace pdr {
func_decl* pred = dit->m_key;
TRACE("pdr", tout << mk_pp(pred, m) << "\n";);
SASSERT(!rels.contains(pred));
e = rels.insert_if_not_there2(pred, alloc(pred_transformer, get_pdr_manager(), pred));
e = rels.insert_if_not_there2(pred, alloc(pred_transformer, *this, get_pdr_manager(), pred));
datalog::rule_vector const& pred_rules = *dit->m_value;
for (unsigned i = 0; i < pred_rules.size(); ++i) {
e->get_data().m_value->add_rule(pred_rules[i]);
@ -1120,7 +1125,7 @@ namespace pdr {
for (; itf != endf; ++itf) {
TRACE("pdr", tout << mk_pp(pred, m) << " " << mk_pp(*itf, m) << "\n";);
if (!rels.find(*itf, pt_user)) {
pt_user = alloc(pred_transformer, get_pdr_manager(), *itf);
pt_user = alloc(pred_transformer, *this, get_pdr_manager(), *itf);
rels.insert(*itf, pt_user);
}
pt_user->add_use(pt);
@ -1179,7 +1184,7 @@ namespace pdr {
void context::add_cover(int level, func_decl* p, expr* property) {
pred_transformer* pt = 0;
if (!m_rels.find(p, pt)) {
pt = alloc(pred_transformer, get_pdr_manager(), p);
pt = alloc(pred_transformer, *this, get_pdr_manager(), p);
m_rels.insert(p, pt);
IF_VERBOSE(10, verbose_stream() << "did not find predicate " << p->get_name() << "\n";);
}
@ -1192,9 +1197,11 @@ namespace pdr {
arith_util a;
bool m_is_bool;
bool m_is_bool_arith;
bool m_has_arith;
bool m_is_dl;
public:
classifier_proc(ast_manager& m, datalog::rule_set& rules):
m(m), a(m), m_is_bool(true), m_is_bool_arith(true) {
m(m), a(m), m_is_bool(true), m_is_bool_arith(true), m_has_arith(false), m_is_dl(false) {
classify(rules);
}
void operator()(expr* e) {
@ -1213,6 +1220,9 @@ namespace pdr {
m_is_bool = false;
}
}
m_has_arith = m_has_arith || a.is_int_real(e);
if (m_is_bool_arith) {
if (!m.is_bool(e) && !a.is_int_real(e)) {
m_is_bool_arith = false;
@ -1235,6 +1245,8 @@ namespace pdr {
bool is_bool_arith() const { return m_is_bool_arith; }
bool is_dl() const { return m_is_dl; }
private:
@ -1249,9 +1261,23 @@ namespace pdr {
classify_pred(mark, r.get_tail(i));
}
for (unsigned i = utsz; i < r.get_tail_size(); ++i) {
quick_for_each_expr(*this, mark, r.get_tail(i));
quick_for_each_expr(*this, mark, r.get_tail(i));
}
}
mark.reset();
m_is_dl = false;
if (m_has_arith) {
ptr_vector<expr> forms;
for (it = rules.begin(); it != end; ++it) {
datalog::rule& r = *(*it);
unsigned utsz = r.get_uninterpreted_tail_size();
for (unsigned i = utsz; i < r.get_tail_size(); ++i) {
forms.push_back(r.get_tail(i));
}
}
m_is_dl = is_difference_logic(m, forms.size(), forms.c_ptr());
}
}
void classify_pred(expr_fast_mark1& mark, app* pred) {
@ -1270,6 +1296,7 @@ namespace pdr {
void context::init_core_generalizers(datalog::rule_set& rules) {
reset_core_generalizers();
classifier_proc classify(m, rules);
m_is_dl = false;
bool use_mc = m_params.get_bool(":use-multicore-generalizer", false);
if (use_mc) {
m_core_generalizers.push_back(alloc(core_multi_generalizer, *this, 0));
@ -1277,12 +1304,16 @@ namespace pdr {
if (m_params.get_bool(":use-farkas", true) && !classify.is_bool()) {
if (m_params.get_bool(":inline-proof-mode", true)) {
m.toggle_proof_mode(PGM_FINE);
m_fparams.m_proof_mode = PGM_FINE;
m_fparams.m_proof_mode = PGM_FINE;
m_fparams.m_arith_bound_prop = BP_NONE;
m_fparams.m_arith_auto_config_simplex = true;
m_fparams.m_arith_propagate_eqs = false;
m_fparams.m_arith_eager_eq_axioms = false;
m_fparams.m_arith_eq_bounds = false;
if (classify.is_dl()) {
m_fparams.m_arith_mode = AS_DIFF_LOGIC;
m_fparams.m_arith_expand_eqs = true;
m_is_dl = true;
}
}
else {
m_core_generalizers.push_back(alloc(core_farkas_generalizer, *this, m, m_fparams));
@ -1630,6 +1661,8 @@ namespace pdr {
*/
void context::create_children(model_node& n) {
SASSERT(n.level() > 0);
bool use_model_generalizer = m_params.get_bool(":use-model-generalizer", false);
// use_model_generalizer = use_model_generalizer || is_dl();
pred_transformer& pt = n.pt();
model_ref M = n.model_ptr();
@ -1637,7 +1670,7 @@ namespace pdr {
expr* T = pt.get_transition(r);
expr* phi = n.state();
IF_VERBOSE(2, verbose_stream() << "Model:\n";
IF_VERBOSE(3, verbose_stream() << "Model:\n";
model_smt2_pp(verbose_stream(), m, *M, 0);
verbose_stream() << "\n";
verbose_stream() << "Transition:\n" << mk_pp(T, m) << "\n";
@ -1649,7 +1682,7 @@ namespace pdr {
forms.push_back(phi);
datalog::flatten_and(forms);
ptr_vector<expr> forms1(forms.size(), forms.c_ptr());
if (m_params.get_bool(":use-model-generalizer", false)) {
if (use_model_generalizer) {
Phi.append(mev.minimize_model(forms1, M));
}
else {
@ -1671,6 +1704,9 @@ namespace pdr {
qe_lite qe(m);
expr_ref phi1 = m_pm.mk_and(Phi);
qe(vars, phi1);
if (!use_model_generalizer) {
reduce_disequalities(*M, 3, phi1);
}
IF_VERBOSE(2,
verbose_stream() << "Vars:\n";

11
lib/pdr_context.h
View file

@ -40,11 +40,13 @@ namespace pdr {
class pred_transformer;
class model_node;
class context;
typedef obj_map<datalog::rule const, qinst*> qinst_map;
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
@ -64,6 +66,7 @@ namespace pdr {
manager& pm; // pdr-manager
ast_manager& m; // manager
context& ctx;
func_decl_ref m_head; // predicate
func_decl_ref_vector m_sig; // signature
@ -106,7 +109,7 @@ namespace pdr {
void add_premises(decl2rel const& pts, unsigned lvl, datalog::rule& rule, expr_ref_vector& r);
public:
pred_transformer(manager& pm, func_decl* head);
pred_transformer(context& ctx, manager& pm, func_decl* head);
~pred_transformer();
void add_rule(datalog::rule* r) { m_rules.push_back(r); }
@ -259,7 +262,6 @@ namespace pdr {
struct model_exception { };
struct inductive_exception {};
class context;
// 'state' is unsatisfiable at 'level' with 'core'.
// Minimize or weaken core.
@ -306,6 +308,7 @@ namespace pdr {
volatile bool m_cancel;
model_converter_ref m_mc;
proof_converter_ref m_pc;
bool m_is_dl;
// Functions used by search.
void solve_impl();
@ -361,9 +364,11 @@ namespace pdr {
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_is_dl; }
void collect_statistics(statistics& st) const;
std::ostream& display(std::ostream& strm) const;

22
lib/pdr_farkas_learner.cpp
View file

@ -204,6 +204,7 @@ namespace pdr {
is_eq = false;
}
}
zero = a.mk_numeral(rational::zero(), a.is_int(res));
if (is_eq) {
res = m.mk_eq(res, zero);
@ -219,8 +220,28 @@ namespace pdr {
proof_ref pr(m);
expr_ref tmp(m);
rw(res, tmp, pr);
fix_dl(tmp);
res = tmp;
}
// patch: swap addends to make static
// features recognize difference constraint.
void fix_dl(expr_ref& r) {
expr* e;
if (m.is_not(r, e)) {
r = e;
fix_dl(r);
r = m.mk_not(r);
return;
}
expr* e1, *e2, *e3, *e4;
if ((m.is_eq(r, e1, e2) || a.is_lt(r, e1, e2) || a.is_gt(r, e1, e2) ||
a.is_le(r, e1, e2) || a.is_ge(r, e1, e2))) {
if (a.is_add(e1, e3, e4) && a.is_mul(e3)) {
r = m.mk_app(to_app(r)->get_decl(), a.mk_add(e4,e3), e2);
}
}
}
};
farkas_learner::farkas_learner(front_end_params& params, ast_manager& outer_mgr)
@ -366,6 +387,7 @@ namespace pdr {
for (unsigned i = 0; i < lemmas.size(); ++i) {
g->assert_expr(lemmas[i].get());
}
expr_ref tmp(m);
model_converter_ref mc;
proof_converter_ref pc;
expr_dependency_ref core(m);

19
lib/pdr_prop_solver.cpp
View file

@ -342,12 +342,23 @@ namespace pdr {
fl.get_lemmas(pr, bs, lemmas);
safe.elim_proxies(lemmas);
fl.simplify_lemmas(lemmas); // redundant
if (m_fparams.m_arith_mode == AS_DIFF_LOGIC &&
!is_difference_logic(m, lemmas.size(), lemmas.c_ptr())) {
IF_VERBOSE(1,
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);
return;
}
IF_VERBOSE(2,
verbose_stream() << "Lemmas\n";
for (unsigned i = 0; i < lemmas.size(); ++i) {
verbose_stream() << mk_pp(lemmas[i].get(), m) << "\n";
});
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);

362
lib/pdr_util.cpp
View file

@ -41,48 +41,51 @@ Notes:
#include "pdr_prop_solver.h"
#include "pdr_util.h"
#include "arith_decl_plugin.h"
#include "expr_replacer.h"
#include "static_features.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, reinterpret_cast<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 << ", ";
}
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, reinterpret_cast<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();
}
res << ")";
return res.str();
}
/////////////////////////
@ -105,7 +108,7 @@ void model_evaluator::assign_value(expr* e, expr* val) {
set_value(e, val);
}
else {
IF_VERBOSE(2, verbose_stream() << "Not evaluated " << mk_pp(e, m) << "\n";);
IF_VERBOSE(3, verbose_stream() << "Not evaluated " << mk_pp(e, m) << "\n";);
TRACE("pdr", tout << "Variable is not tracked: " << mk_pp(e, m) << "\n";);
set_x(e);
}
@ -673,8 +676,7 @@ void model_evaluator::eval_basic(app* e) {
}
bool model_evaluator::check_model(ptr_vector<expr> const& formulas) {
ptr_vector<expr> todo;
assign_vector_with_casting(todo, formulas);
ptr_vector<expr> todo(formulas);
while (!todo.empty()) {
expr * curr_e = todo.back();
@ -735,69 +737,235 @@ bool model_evaluator::check_model(ptr_vector<expr> const& formulas) {
return !has_x;
}
func_decl * mk_store(ast_manager& m, sort * arr_sort)
{
family_id array_fid = m.get_family_id(symbol("array"));
unsigned num_params = arr_sort->get_num_parameters();
ptr_vector<sort> domain;
domain.push_back(arr_sort);
//we push params of the array as remaining arguments of the store. The first
//num_params-1 parameters are indices and the last one is the range of the array
for (unsigned i=0; i<num_params; ++i) {
domain.push_back(to_sort(arr_sort->get_parameter(i).get_ast()));
func_decl * mk_store(ast_manager& m, sort * arr_sort)
{
family_id array_fid = m.get_family_id(symbol("array"));
unsigned num_params = arr_sort->get_num_parameters();
ptr_vector<sort> domain;
domain.push_back(arr_sort);
//we push params of the array as remaining arguments of the store. The first
//num_params-1 parameters are indices and the last one is the range of the array
for (unsigned i=0; i<num_params; ++i) {
domain.push_back(to_sort(arr_sort->get_parameter(i).get_ast()));
}
return m.mk_func_decl(array_fid, OP_STORE,
arr_sort->get_num_parameters(), arr_sort->get_parameters(),
domain.size(), domain.c_ptr(), arr_sort);
}
return m.mk_func_decl(array_fid, OP_STORE,
arr_sort->get_num_parameters(), arr_sort->get_parameters(),
domain.size(), domain.c_ptr(), arr_sort);
}
void get_as_array_value(const model_core & mdl, expr * arr_e, expr_ref& res) {
ast_manager& m = mdl.get_manager();
array_util pl(m);
SASSERT(pl.is_as_array(arr_e));
app * arr = to_app(arr_e);
unsigned sz = 0;
func_decl_ref f(pl.get_as_array_func_decl(arr), m);
sort * arr_sort = arr->get_decl()->get_range();
func_interp* g = mdl.get_func_interp(f);
res = pl.mk_const_array(arr_sort, g->get_else());
void get_as_array_value(const model_core & mdl, expr * arr_e, expr_ref& res) {
ast_manager& m = mdl.get_manager();
array_util pl(m);
SASSERT(pl.is_as_array(arr_e));
app * arr = to_app(arr_e);
unsigned sz = 0;
func_decl_ref f(pl.get_as_array_func_decl(arr), m);
sort * arr_sort = arr->get_decl()->get_range();
func_interp* g = mdl.get_func_interp(f);
res = pl.mk_const_array(arr_sort, g->get_else());
unsigned arity = f->get_arity();
sz = g->num_entries();
if (sz) {
func_decl_ref store_fn(mk_store(m, arr_sort), m);
ptr_vector<expr> store_args;
for (unsigned i = 0; i < sz; ++i) {
const func_entry * fe = g->get_entry(i);
store_args.reset();
store_args.push_back(res);
store_args.append(arity, fe->get_args());
store_args.push_back(fe->get_result());
res = m.mk_app(store_fn, store_args.size(), store_args.c_ptr());
unsigned arity = f->get_arity();
sz = g->num_entries();
if (sz) {
func_decl_ref store_fn(mk_store(m, arr_sort), m);
ptr_vector<expr> store_args;
for (unsigned i = 0; i < sz; ++i) {
const func_entry * fe = g->get_entry(i);
store_args.reset();
store_args.push_back(res);
store_args.append(arity, fe->get_args());
store_args.push_back(fe->get_result());
res = m.mk_app(store_fn, store_args.size(), store_args.c_ptr());
}
}
}
}
void get_value_from_model(const model_core & mdl, func_decl * f, expr_ref& res) {
SASSERT(f->get_arity()==0);
ast_manager& m = mdl.get_manager();
res = mdl.get_const_interp(f);
array_util pl(m);
if (pl.is_as_array(res)) {
get_as_array_value(mdl, res, res);
void get_value_from_model(const model_core & mdl, func_decl * f, expr_ref& res) {
SASSERT(f->get_arity()==0);
ast_manager& m = mdl.get_manager();
res = mdl.get_const_interp(f);
array_util pl(m);
if (pl.is_as_array(res)) {
get_as_array_value(mdl, res, res);
}
}
}
void reduce_disequalities(model& model, unsigned threshold, expr_ref& fml) {
ast_manager& m = fml.get_manager();
expr_ref_vector conjs(m);
datalog::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 ite_hoister {
ast_manager& m;
public:
ite_hoister(ast_manager& m): m(m) {}
br_status mk_app_core(func_decl* f, unsigned num_args, expr* const* args, expr_ref& result) {
for (unsigned i = 0; i < num_args; ++i) {
expr* c, *t, *e;
if (!m.is_bool(args[i]) && m.is_ite(args[i], c, t, e)) {
expr_ref e1(m), e2(m);
ptr_vector<expr> args1(num_args, args);
args1[i] = t;
e1 = m.mk_app(f, num_args, args1.c_ptr());
args1[i] = e;
e2 = m.mk_app(f, num_args, args1.c_ptr());
result = m.mk_ite(c, e1, e2);
return BR_REWRITE3;
}
}
return BR_FAILED;
}
};
struct ite_hoister_cfg: public default_rewriter_cfg {
ite_hoister 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);
}
ite_hoister_cfg(ast_manager & m, params_ref const & p):m_r(m) {}
};
class ite_hoister_star : public rewriter_tpl<ite_hoister_cfg> {
ite_hoister_cfg m_cfg;
public:
ite_hoister_star(ast_manager & m, params_ref const & p):
rewriter_tpl<ite_hoister_cfg>(m, false, m_cfg),
m_cfg(m, p) {}
};
template class rewriter_tpl<ite_hoister_cfg>;
class scoped_no_proof {
ast_manager& m;
proof_gen_mode m_mode;
public:
scoped_no_proof(ast_manager& m): m(m) {
m_mode = m.proof_mode();
m.toggle_proof_mode(PGM_DISABLED);
}
~scoped_no_proof() {
m.toggle_proof_mode(m_mode);
}
};
void hoist_non_bool_if(expr_ref& fml) {
ast_manager& m = fml.get_manager();
scoped_no_proof _sp(m);
params_ref p;
ite_hoister_star ite_rw(m, p);
expr_ref tmp(m);
ite_rw(fml, tmp);
fml = tmp;
}
class test_diff_logic {
ast_manager& m;
arith_util a;
bool m_is_dl;
public:
test_diff_logic(ast_manager& m): m(m), a(m), m_is_dl(true) {}
void operator()(expr* e) {
if (m_is_dl && a.is_arith_expr(e) && !a.is_numeral(e) &&
!a.is_add(e) && !a.is_mul(e) && !m.is_bool(e)) {
m_is_dl = false;
}
}
bool is_dl() const { return m_is_dl; }
};
bool is_difference_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls) {
static_features st(m);
st.collect(num_fmls, fmls);
if (st.m_num_arith_eqs != st.m_num_diff_eqs ||
st.m_num_arith_terms != st.m_num_diff_terms ||
st.m_num_arith_ineqs != st.m_num_diff_ineqs) {
return false;
}
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();
}
}

302
lib/pdr_util.h
View file

@ -25,231 +25,123 @@ Revision History:
#include "obj_hashtable.h"
#include "ref_vector.h"
#include "simplifier.h"
#include "th_rewriter.h"
#include "trace.h"
#include "vector.h"
#include "arith_decl_plugin.h"
#include "bv_decl_plugin.h"
struct front_end_params;
class model;
class model_core;
namespace pdr {
class manager;
class prop_solver;
/**
* 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);
template<class TgtVect, class SrcVect>
void assign_vector_with_casting(TgtVect& tgt, const SrcVect& src)
{
SASSERT(static_cast<const void*>(&tgt)!=static_cast<const void*>(&src));
tgt.reset();
typename SrcVect::data const * begin = src.c_ptr();
typename SrcVect::data const * end = begin + src.size();
for(typename SrcVect::data const * it = begin; it!=end; it++)
{
tgt.push_back(static_cast<typename TgtVect::data>(*it));
}
/* tgt.reset();
typename SrcVect::const_iterator end = src.end();
for(typename SrcVect::const_iterator it = src.begin(); it!=end; it++)
{
tgt.push_back(static_cast<typename TgtVect::data>(*it));
}*/
}
template<class TgtType, class SrcType, class Mgr>
void append_ref_vector_with_casting(ref_vector<TgtType,Mgr> & tgt, const ref_vector<SrcType,Mgr> & src)
{
SASSERT(static_cast<const void*>(&tgt)!=static_cast<const void*>(&src));
SrcType * const * begin = src.c_ptr();
SrcType * const * end = begin + src.size();
for(SrcType * const * it = begin; it!=end; it++)
{
tgt.push_back(static_cast<TgtType *>(*it));
}
}
template<class TgtType, class SrcType, class Mgr>
void assign_ref_vector_with_casting(ref_vector<TgtType,Mgr> & tgt, const ref_vector<SrcType,Mgr> & src)
{
SASSERT(static_cast<const void*>(&tgt)!=static_cast<const void*>(&src));
tgt.reset();
append_ref_vector_with_casting(tgt, src);
}
template<class T,class M>
ref_vector<T,M>& assign_ref_vector(ref_vector<T,M> & tgt, const ref_vector<T,M> & src)
{
SASSERT(static_cast<const void*>(&tgt)!=static_cast<const void*>(&src));
//we support assignment only on vectors with the same manager
SASSERT(&tgt.get_manager()==&src.get_manager());
tgt.reset();
tgt.append(src);
return tgt;
}
template<class Type, class Mgr, class Comp>
void sort_ref_vect(ref_vector<Type,Mgr> & vect, Comp cmp)
{
Type * * begin = vect.c_ptr();
Type * * end = begin + vect.size();
std::sort(begin, end, cmp);
}
/**
Into res put all elements that are in left but not in right.
This function can change the order of elements in left.
*/
template<class Type, class Mgr, class Comp>
void vect_set_diff(ref_vector<Type,Mgr> & left, ref_vector<Type,Mgr> & right,
ref_vector<Type,Mgr> & res, Comp cmp)
{
sort_ref_vect(left, cmp);
sort_ref_vect(right, cmp);
res.reset();
Type * const * lbegin = left.c_ptr();
Type * const * lend = lbegin + left.size();
Type * const * lit = lbegin;
Type * const * rbegin = right.c_ptr();
Type * const * rend = rbegin + right.size();
Type * const * rit = rbegin;
while(lit!=lend) {
while(rit!=rend && lit!=lend && *rit==*lit) {
++rit;
++lit;
}
if(lit==lend) {
return;
}
while(rit!=rend && cmp(*rit, *lit)) {
++rit;
}
while(lit!=lend && (rit==rend || cmp(*lit, *rit))) {
res.push_back(*lit);
++lit;
}
}
}
/**
Ensure all elements from src are in tgt
This function can change the order of elements in tgt and src.
*/
template<class Type, class Mgr, class Comp>
void vect_set_union(ref_vector<Type,Mgr> & tgt, ref_vector<Type,Mgr> & src, Comp cmp)
{
ref_vector<Type,Mgr> diff(tgt.get_manager());
vect_set_diff(src, tgt, diff, cmp);
tgt.append(diff);
}
class model_evaluator {
ast_manager& m;
arith_util m_arith;
bv_util m_bv;
obj_map<expr,rational> m_numbers;
expr_ref_vector m_refs;
obj_map<expr, expr*> m_values;
model_ref m_model;
//00 -- non-visited
//01 -- X
//10 -- false
//11 -- true
ast_fast_mark1 m1;
ast_fast_mark2 m2;
unsigned m_level1;
unsigned m_level2;
expr_mark m_visited;
void reset();
void setup_model(model_ref& model);
void assign_value(expr* e, expr* v);
void collect(ptr_vector<expr> const& formulas, ptr_vector<expr>& tocollect);
void process_formula(app* e, ptr_vector<expr>& todo, ptr_vector<expr>& tocollect);
expr_ref_vector prune_by_cone_of_influence(ptr_vector<expr> const & formulas);
void eval_arith(app* e);
void eval_basic(app* e);
void eval_iff(app* e, expr* arg1, expr* arg2);
void inherit_value(expr* e, expr* v);
//00 -- non-visited
//01 -- X
//10 -- false
//11 -- true
inline bool is_unknown(expr* x) { return !m1.is_marked(x) && !m2.is_marked(x); }
inline void set_unknown(expr* x) { m1.reset_mark(x); m2.reset_mark(x); }
inline bool is_x(expr* x) { return !m1.is_marked(x) && m2.is_marked(x); }
inline bool is_false(expr* x) { return m1.is_marked(x) && !m2.is_marked(x); }
inline bool is_true(expr* x) { return m1.is_marked(x) && m2.is_marked(x); }
inline void set_x(expr* x) { SASSERT(is_unknown(x)); m2.mark(x); }
inline void set_v(expr* x) { SASSERT(is_unknown(x)); m1.mark(x); }
inline void set_false(expr* x) { SASSERT(is_unknown(x)); m1.mark(x); }
inline void set_true(expr* x) { SASSERT(is_unknown(x)); m1.mark(x); m2.mark(x); }
inline void set_bool(expr* x, bool v) { if (v) { set_true(x); } else { set_false(x); } }
inline rational const& get_number(expr* x) const { return m_numbers.find(x); }
inline void set_number(expr* x, rational const& v) { set_v(x); TRACE("pdr_verbose", tout << mk_pp(x,m) << " " << v << "\n";); m_numbers.insert(x,v); }
inline expr* get_value(expr* x) { return m_values.find(x); }
inline void set_value(expr* x, expr* v) { set_v(x); m_refs.push_back(v); m_values.insert(x, v); }
/**
* 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;
protected:
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);
class model_evaluator {
ast_manager& m;
arith_util m_arith;
obj_map<expr,rational> m_numbers;
expr_ref_vector m_refs;
obj_map<expr, expr*> m_values;
model_ref m_model;
//00 -- non-visited
//01 -- X
//10 -- false
//11 -- true
ast_fast_mark1 m1;
ast_fast_mark2 m2;
unsigned m_level1;
unsigned m_level2;
expr_mark m_visited;
bool check_model(ptr_vector<expr> const & formulas);
void reset();
void setup_model(model_ref& model);
void assign_value(expr* e, expr* v);
void collect(ptr_vector<expr> const& formulas, ptr_vector<expr>& tocollect);
void process_formula(app* e, ptr_vector<expr>& todo, ptr_vector<expr>& tocollect);
expr_ref_vector prune_by_cone_of_influence(ptr_vector<expr> const & formulas);
void eval_arith(app* e);
void eval_basic(app* e);
void eval_iff(app* e, expr* arg1, expr* arg2);
void inherit_value(expr* e, expr* v);
inline bool is_unknown(expr* x) { return !m1.is_marked(x) && !m2.is_marked(x); }
inline void set_unknown(expr* x) { m1.reset_mark(x); m2.reset_mark(x); }
inline bool is_x(expr* x) { return !m1.is_marked(x) && m2.is_marked(x); }
inline bool is_false(expr* x) { return m1.is_marked(x) && !m2.is_marked(x); }
inline bool is_true(expr* x) { return m1.is_marked(x) && m2.is_marked(x); }
inline void set_x(expr* x) { SASSERT(is_unknown(x)); m2.mark(x); }
inline void set_v(expr* x) { SASSERT(is_unknown(x)); m1.mark(x); }
inline void set_false(expr* x) { SASSERT(is_unknown(x)); m1.mark(x); }
inline void set_true(expr* x) { SASSERT(is_unknown(x)); m1.mark(x); m2.mark(x); }
inline void set_bool(expr* x, bool v) { if (v) { set_true(x); } else { set_false(x); } }
inline rational const& get_number(expr* x) const { return m_numbers.find(x); }
inline void set_number(expr* x, rational const& v) {
set_v(x); TRACE("pdr_verbose", tout << mk_pp(x,m) << " " << v << "\n";); m_numbers.insert(x,v);
}
inline expr* get_value(expr* x) { return m_values.find(x); }
inline void set_value(expr* x, expr* v) { set_v(x); m_refs.push_back(v); m_values.insert(x, v); }
bool check_model(ptr_vector<expr> const & formulas);
public:
model_evaluator(ast_manager& m) : m(m), m_arith(m), m_refs(m) {}
/**
\brief extract equalities from model that suffice to satisfy formula.
\pre model satisfies formulas
*/
expr_ref_vector minimize_model(ptr_vector<expr> const & formulas, model_ref& mdl);
/**
\brief extract literals from formulas that satisfy formulas.
public:
model_evaluator(ast_manager& m) : m(m), m_arith(m), m_bv(m), m_refs(m) {}
\pre model satisfies formulas
*/
expr_ref_vector minimize_literals(ptr_vector<expr> const & formulas, model_ref& mdl);
// for_each_expr visitor.
void operator()(expr* e) {}
};
void get_value_from_model(const model_core & mdl, func_decl * f, expr_ref& res);
/**
\brief extract equalities from model that suffice to satisfy formula.
\pre model satisfies formulas
*/
expr_ref_vector minimize_model(ptr_vector<expr> const & formulas, model_ref& mdl);
\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 extract literals from formulas that satisfy formulas.
\brief hoist non-boolean if expressions.
*/
void hoist_non_bool_if(expr_ref& fml);
\pre model satisfies formulas
*/
expr_ref_vector minimize_literals(ptr_vector<expr> const & formulas, model_ref& mdl);
// for_each_expr visitor.
void operator()(expr* e) {}
};
void get_value_from_model(const model_core & mdl, func_decl * f, expr_ref& res);
bool is_difference_logic(ast_manager& m, unsigned num_fmls, expr* const* fmls);
}

19
lib/static_features.cpp
View file

@ -130,20 +130,23 @@ bool static_features::is_diff_atom(expr const * e) const {
return false;
SASSERT(to_app(e)->get_num_args() == 2);
expr * lhs = to_app(e)->get_arg(0);
SASSERT(is_numeral(to_app(e)->get_arg(1)));
expr * rhs = to_app(e)->get_arg(1);
if (!is_arith_expr(lhs) && !is_arith_expr(rhs))
return true;
if (!is_numeral(rhs))
return false;
// lhs can be 'x' or '(+ x (* -1 y))'
if (!is_arith_expr(lhs))
return true;
SASSERT(is_app(lhs));
// lhs must be (+ x (* -1 y))
if (to_app(lhs)->get_decl_kind() != OP_ADD || to_app(lhs)->get_num_args() != 2)
return false;
expr* arg1, *arg2;
if (!m_autil.is_add(lhs, arg1, arg2))
return false;
// x
if (is_arith_expr(to_app(lhs)->get_arg(0)))
if (is_arith_expr(arg1))
return false;
expr * arg2 = to_app(lhs)->get_arg(1);
// arg2: (* -1 y)
return m_autil.is_mul(arg2) && to_app(arg2)->get_num_args() == 2 && is_minus_one(to_app(arg2)->get_arg(0)) && !is_arith_expr(to_app(arg2)->get_arg(1));
expr* m1, *m2;
return m_autil.is_mul(arg2, m1, m2) && is_minus_one(m1) && !is_arith_expr(m2);
}
bool static_features::is_gate(expr const * e) const {

8
lib/theory_diff_logic.cpp
View file

@ -16,14 +16,6 @@ Author:
Revision History:
TODO:
- port diff_logic.*
- port theory_diff_logic
- fix theory propagation
- fix/add equality propagation
- fix relaxation.
--*/
#include "theory_diff_logic.h"

45
lib/theory_diff_logic.h
View file

@ -16,30 +16,6 @@ Author:
Revision History:
TODO:
- check regressions with smt::solver.
- what should be done properly (during internalization) for reflect()
- fix theory propagation:
- x <= y + 2, then x <= y + 3
- x = y, then x <= y + 2
- x = y, x <= z <= y, then x = z
- fix/add equality propagation
- add relaxation (somewhat easy)
- Currently stored explanation in edges is stored at creation time
(not at propagation time).
Is this flexible enough for processing equalities?
- eq_justification present in smt::context when calling new_eq_eh.
pass such to the edge?
- context::assume_eq is absent.
- context::add_eq and context::push_eq are protected. Cannot propagate equalities back to core.
-
--*/
@ -76,13 +52,7 @@ namespace smt {
unsigned m_num_core2th_diseqs;
unsigned m_num_core2th_new_diseqs;
void reset() {
m_num_conflicts = 0;
m_num_assertions = 0;
m_num_th2core_prop = 0;
m_num_th2core_eqs = 0;
m_num_core2th_eqs = 0;
m_num_core2th_diseqs = 0;
m_num_core2th_new_diseqs = 0;
memset(this, 0, sizeof(*this));
}
theory_diff_logic_statistics() {
reset();
@ -93,17 +63,12 @@ namespace smt {
public:
dl_conflict(region & r, unsigned nls, literal const * lits): simple_justification(r, nls, lits) { }
virtual proof * mk_proof(conflict_resolution & cr) { NOT_IMPLEMENTED_YET(); return 0; }
virtual proof * mk_proof(conflict_resolution & cr) {
NOT_IMPLEMENTED_YET();
return 0;
}
};
class dl_propagate : public simple_justification {
public:
dl_propagate(region & r, unsigned nls, literal const * lits): simple_justification(r, nls, lits) { }
virtual proof * mk_proof(conflict_resolution & cr) { NOT_IMPLEMENTED_YET(); return 0; }
};
template<typename Ext>
class theory_diff_logic : public theory, private Ext {

37
lib/theory_diff_logic_def.h
View file

@ -403,18 +403,23 @@ void theory_diff_logic<Ext>::del_atoms(unsigned old_size) {
template<typename Ext>
bool theory_diff_logic<Ext>::is_negative(app* n, app*& m) {
if (!m_util.is_mul(n) || n->get_num_args() != 2) {
expr* a0, *a1, *a2;
rational r;
if (!m_util.is_mul(n, a0, a1)) {
return false;
}
rational r;
expr* a0 = n->get_arg(0);
expr* a1 = n->get_arg(1);
if (m_util.is_numeral(a1)) {
std::swap(a0, a1);
}
if (m_util.is_numeral(a0, r) && r.is_minus_one() && is_app(a1)) {
m = to_app(a1);
return true;
}
if (m_util.is_numeral(a1, r) && r.is_minus_one() && is_app(a0)) {
m = to_app(a0);
if (m_util.is_uminus(a1)) {
std::swap(a0, a1);
}
if (m_util.is_uminus(a0, a2) && m_util.is_numeral(a2, r) && r.is_one() && is_app(a1)) {
m = to_app(a1);
return true;
}
return false;
@ -615,7 +620,12 @@ void theory_diff_logic<Ext>::new_edge(dl_var src, dl_var dst, unsigned num_edges
justification * js = 0;
if (get_manager().proofs_enabled()) {
js = 0; // TBD?
vector<parameter> params;
params.push_back(parameter(symbol("farkas")));
params.resize(lits.size()+1, parameter(rational(1)));
js = new (ctx.get_region()) theory_lemma_justification(get_id(), ctx,
lits.size(), lits.c_ptr(),
params.size(), params.c_ptr());
}
clause_del_eh* del_eh = alloc(theory_diff_logic_del_eh, *this);
clause* cls = ctx.mk_clause(lits.size(), lits.c_ptr(), js, CLS_AUX_LEMMA, del_eh);
@ -675,7 +685,18 @@ void theory_diff_logic<Ext>::set_neg_cycle_conflict() {
ctx.display_lemma_as_smt_problem(lits.size(), lits.c_ptr(), false_literal, logic);
}
ctx.set_conflict(ctx.mk_justification(dl_conflict(r, lits.size(), lits.c_ptr())));
vector<parameter> params;
if (get_manager().proofs_enabled()) {
params.push_back(parameter(symbol("farkas")));
params.resize(lits.size()+1, parameter(rational(1)));
}
ctx.set_conflict(
ctx.mk_justification(
ext_theory_conflict_justification(
get_id(), ctx.get_region(),
lits.size(), lits.c_ptr(), 0, 0, params.size(), params.c_ptr())));
}
template<typename Ext>