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fixes #186, remove ite-lifting from opt_context to detect weighted maxsat

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2015-08-06 11:52:59 +02:00
parent e59ec5fefd
commit f96c0b6963
8 changed files with 109 additions and 22 deletions
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18
src/ast/ast.cpp
View file

@ -2038,11 +2038,13 @@ app * ast_manager::mk_app_core(func_decl * decl, unsigned num_args, expr * const
}
}
}
check_args(decl, num_args, new_args.c_ptr());
SASSERT(new_args.size() == num_args);
new_node = new (mem) app(decl, num_args, new_args.c_ptr());
r = register_node(new_node);
}
else {
check_args(decl, num_args, args);
new_node = new (mem) app(decl, num_args, args);
r = register_node(new_node);
}
@ -2064,6 +2066,22 @@ app * ast_manager::mk_app_core(func_decl * decl, unsigned num_args, expr * const
return r;
}
void ast_manager::check_args(func_decl* f, unsigned n, expr* const* es) {
for (unsigned i = 0; i < n; i++) {
sort * actual_sort = get_sort(es[i]);
sort * expected_sort = f->is_associative() ? f->get_domain(0) : f->get_domain(i);
if (expected_sort != actual_sort) {
std::ostringstream buffer;
buffer << "Sort mismatch at argument #" << (i+1)
<< " for function " << mk_pp(f,*this)
<< " supplied sort is "
<< mk_pp(actual_sort, *this);
throw ast_exception(buffer.str().c_str());
}
}
}
inline app * ast_manager::mk_app_core(func_decl * decl, expr * arg1, expr * arg2) {
expr * args[2] = { arg1, arg2 };
return mk_app_core(decl, 2, args);

3
src/ast/ast.h
View file

@ -1460,6 +1460,9 @@ protected:
bool coercion_needed(func_decl * decl, unsigned num_args, expr * const * args);
void check_args(func_decl* f, unsigned n, expr* const* es);
public:
ast_manager(proof_gen_mode = PGM_DISABLED, char const * trace_file = 0, bool is_format_manager = false);
ast_manager(proof_gen_mode, std::fstream * trace_stream, bool is_format_manager = false);

6
src/ast/pb_decl_plugin.cpp
View file

@ -280,3 +280,9 @@ bool pb_util::has_unit_coefficients(func_decl* f) const {
}
return true;
}
app* pb_util::mk_fresh_bool() {
symbol name = m.mk_fresh_var_name("pb");
func_decl_info info(m_fid, OP_PB_AUX_BOOL, 0, 0);
return m.mk_const(m.mk_func_decl(name, 0, (sort *const*)0, m.mk_bool_sort(), info));
}

5
src/ast/pb_decl_plugin.h
View file

@ -35,6 +35,7 @@ enum pb_op_kind {
OP_PB_LE, // pseudo-Boolean <= (generalizes at_most_k)
OP_PB_GE, // pseudo-Boolean >=
OP_PB_EQ, // equality
OP_PB_AUX_BOOL, // auxiliary internal Boolean variable.
LAST_PB_OP
};
@ -71,6 +72,7 @@ public:
virtual func_decl * mk_func_decl(decl_kind k, unsigned num_parameters, parameter const * parameters,
unsigned arity, sort * const * domain, sort * range);
virtual void get_op_names(svector<builtin_name> & op_names, symbol const & logic);
};
@ -101,6 +103,7 @@ public:
bool is_ge(func_decl* a) const;
bool is_ge(expr* a) const { return is_app(a) && is_ge(to_app(a)->get_decl()); }
bool is_ge(expr* a, rational& k) const;
bool is_aux_bool(expr* e) const { return is_app_of(e, m_fid, OP_PB_AUX_BOOL); }
rational get_coeff(expr* a, unsigned index) const { return get_coeff(to_app(a)->get_decl(), index); }
rational get_coeff(func_decl* a, unsigned index) const;
bool has_unit_coefficients(func_decl* f) const;
@ -111,6 +114,8 @@ public:
bool is_eq(expr* e) const { return is_app(e) && is_eq(to_app(e)->get_decl()); }
bool is_eq(expr* e, rational& k) const;
app* mk_fresh_bool();
private:
rational to_rational(parameter const& p) const;

64
src/opt/opt_context.cpp
View file

@ -31,7 +31,6 @@ Notes:
#include "propagate_values_tactic.h"
#include "solve_eqs_tactic.h"
#include "elim_uncnstr_tactic.h"
#include "elim_term_ite_tactic.h"
#include "tactical.h"
#include "model_smt2_pp.h"
#include "card2bv_tactic.h"
@ -652,7 +651,6 @@ namespace opt {
and_then(mk_simplify_tactic(m),
mk_propagate_values_tactic(m),
mk_solve_eqs_tactic(m),
mk_elim_term_ite_tactic(m),
// NB: mk_elim_uncstr_tactic(m) is not sound with soft constraints
mk_simplify_tactic(m));
opt_params optp(m_params);
@ -660,14 +658,16 @@ namespace opt {
if (optp.elim_01()) {
tac2 = mk_elim01_tactic(m);
tac3 = mk_lia2card_tactic(m);
tac4 = mk_elim_term_ite_tactic(m);
params_ref lia_p;
lia_p.set_bool("compile_equality", optp.pb_compile_equality());
tac3->updt_params(lia_p);
set_simplify(and_then(tac0.get(), tac2.get(), tac3.get(), tac4.get()));
set_simplify(and_then(tac0.get(), tac2.get(), tac3.get(), mk_simplify_tactic(m)));
}
else {
set_simplify(tac0.get());
tactic_ref tac1 =
and_then(tac0.get(),
mk_simplify_tactic(m));
set_simplify(tac1.get());
}
proof_converter_ref pc;
expr_dependency_ref core(m);
@ -875,9 +875,11 @@ namespace opt {
TRACE("opt", tout << "maxsat: " << id << " offset:" << offset << "\n";);
}
else if (is_maximize(fml, tr, orig_term, index)) {
purify(tr);
m_objectives[index].m_term = tr;
}
else if (is_minimize(fml, tr, orig_term, index)) {
purify(tr);
m_objectives[index].m_term = tr;
m_objectives[index].m_adjust_value.set_negate(true);
}
@ -887,6 +889,50 @@ namespace opt {
}
}
void context::purify(app_ref& term) {
filter_model_converter_ref fm;
if (m_arith.is_add(term)) {
expr_ref_vector args(m);
unsigned sz = term->get_num_args();
for (unsigned i = 0; i < sz; ++i) {
expr* arg = term->get_arg(i);
if (is_mul_const(arg)) {
args.push_back(arg);
}
else {
args.push_back(purify(fm, arg));
}
}
term = m_arith.mk_add(args.size(), args.c_ptr());
}
else if (m_arith.is_arith_expr(term) && !is_mul_const(term)) {
TRACE("opt", tout << "Purifying " << term << "\n";);
term = purify(fm, term);
}
if (fm) {
m_model_converter = concat(m_model_converter.get(), fm.get());
}
}
bool context::is_mul_const(expr* e) {
expr* e1, *e2;
return
is_uninterp_const(e) ||
m_arith.is_numeral(e) ||
(m_arith.is_mul(e, e1, e2) && m_arith.is_numeral(e1) && is_uninterp_const(e2)) ||
(m_arith.is_mul(e, e2, e1) && m_arith.is_numeral(e1) && is_uninterp_const(e2));
}
app* context::purify(filter_model_converter_ref& fm, expr* term) {
std::ostringstream out;
out << mk_pp(term, m);
app* q = m.mk_fresh_const(out.str().c_str(), m.get_sort(term));
if (!fm) fm = alloc(filter_model_converter, m);
m_hard_constraints.push_back(m.mk_eq(q, term));
fm->insert(q->get_decl());
return q;
}
/**
To select the proper theory solver we have to ensure that all theory
symbols from soft constraints are reflected in the hard constraints.
@ -894,7 +940,7 @@ namespace opt {
- filter "obj" from generated model.
*/
void context::mk_atomic(expr_ref_vector& terms) {
ref<filter_model_converter> fm;
filter_model_converter_ref fm;
for (unsigned i = 0; i < terms.size(); ++i) {
expr_ref p(terms[i].get(), m);
app_ref q(m);
@ -902,11 +948,7 @@ namespace opt {
terms[i] = p;
}
else {
q = m.mk_fresh_const("obj", m.mk_bool_sort());
terms[i] = q;
m_hard_constraints.push_back(m.mk_iff(p, q));
if (!fm) fm = alloc(filter_model_converter, m);
fm->insert(q->get_decl());
terms[i] = purify(fm, p);
}
}
if (fm) {

3
src/opt/opt_context.h
View file

@ -244,6 +244,9 @@ namespace opt {
bool is_maxsat(expr* fml, expr_ref_vector& terms,
vector<rational>& weights, rational& offset, bool& neg,
symbol& id, unsigned& index);
void purify(app_ref& term);
app* purify(filter_model_converter_ref& fm, expr* e);
bool is_mul_const(expr* e);
expr* mk_maximize(unsigned index, app* t);
expr* mk_minimize(unsigned index, app* t);
expr* mk_maxsat(unsigned index, unsigned num_fmls, expr* const* fmls);

30
src/smt/theory_pb.cpp
View file

@ -410,18 +410,24 @@ namespace smt {
}
bool theory_pb::internalize_atom(app * atom, bool gate_ctx) {
SASSERT(m_util.is_at_most_k(atom) || m_util.is_le(atom) ||
m_util.is_ge(atom) || m_util.is_at_least_k(atom) ||
m_util.is_eq(atom));
context& ctx = get_context();
if (ctx.b_internalized(atom)) {
return false;
}
SASSERT(!ctx.b_internalized(atom));
m_stats.m_num_predicates++;
if (m_util.is_aux_bool(atom)) {
bool_var abv = ctx.mk_bool_var(atom);
ctx.set_var_theory(abv, get_id());
return true;
}
SASSERT(m_util.is_at_most_k(atom) || m_util.is_le(atom) ||
m_util.is_ge(atom) || m_util.is_at_least_k(atom) ||
m_util.is_eq(atom));
unsigned num_args = atom->get_num_args();
bool_var abv = ctx.mk_bool_var(atom);
ctx.set_var_theory(abv, get_id());
@ -617,15 +623,15 @@ namespace smt {
// function internalize, where enodes for each argument
// is available.
if (!has_bv) {
expr_ref tmp(m), fml(m);
tmp = m.mk_fresh_const("pb_proxy",m.mk_bool_sort());
app_ref tmp(m), fml(m);
pb_util pb(m);
tmp = pb.mk_fresh_bool();
fml = m.mk_iff(tmp, arg);
TRACE("pb", tout << "create proxy " << fml << "\n";);
ctx.internalize(fml, false);
SASSERT(ctx.b_internalized(tmp));
bv = ctx.get_bool_var(tmp);
SASSERT(null_theory_var == ctx.get_var_theory(bv));
ctx.set_var_theory(bv, get_id());
SASSERT(get_id() == ctx.get_var_theory(bv));
literal lit(ctx.get_bool_var(fml));
ctx.mk_th_axiom(get_id(), 1, &lit);
ctx.mark_as_relevant(tmp.get());
@ -1148,17 +1154,19 @@ namespace smt {
context& ctx;
ast_manager& m;
theory_pb& th;
pb_util pb;
typedef smt::literal literal;
typedef smt::literal_vector literal_vector;
psort_expr(context& c, theory_pb& th):
ctx(c),
m(c.get_manager()),
th(th) {}
th(th),
pb(m) {}
literal fresh() {
app_ref y(m);
y = m.mk_fresh_const("y", m.mk_bool_sort());
y = pb.mk_fresh_bool();
return literal(ctx.mk_bool_var(y));
}

2
src/tactic/filter_model_converter.h
View file

@ -45,4 +45,6 @@ public:
virtual model_converter * translate(ast_translation & translator);
};
typedef ref<filter_model_converter> filter_model_converter_ref;
#endif