void mk_coalesce::merge_rules(rule_ref& tgt, rule const& src) {
SASSERT(same_body(*tgt.get(), src));
m_sub1.reset();
m_sub2.reset();
m_idx = 0;
app_ref pred(m), head(m);
expr_ref fml1(m), fml2(m), fml(m);
app_ref_vector tail(m);
ptr_vector<sort> sorts1, sorts2;
expr_ref_vector conjs1(m), conjs(m);
rule_ref res(rm);
bool_rewriter bwr(m);
svector<bool> is_neg;
tgt->get_vars(sorts1);
src.get_vars(sorts2);
mk_pred(head, src.get_head(), tgt->get_head());
for (unsigned i = 0; i < src.get_uninterpreted_tail_size(); ++i) {
mk_pred(pred, src.get_tail(i), tgt->get_tail(i));
tail.push_back(pred);
is_neg.push_back(src.is_neg_tail(i));
}
extract_conjs(m_sub1, src, fml1);
extract_conjs(m_sub2, *tgt.get(), fml2);
bwr.mk_or(fml1, fml2, fml);
SASSERT(is_app(fml));
tail.push_back(to_app(fml));
is_neg.push_back(false);
res = rm.mk(head, tail.size(), tail.c_ptr(), is_neg.c_ptr(), tgt->name());
if (m_ctx.generate_proof_trace()) {
src.to_formula(fml1);
tgt->to_formula(fml2);
res->to_formula(fml);
#if 0
sort* ps = m.mk_proof_sort();
sort* domain[3] = { ps, ps, m.mk_bool_sort() };
func_decl* merge = m.mk_func_decl(symbol("merge-clauses"), 3, domain, ps); // TBD: ad-hoc proof rule
expr* args[3] = { m.mk_asserted(fml1), m.mk_asserted(fml2), fml };
// ...m_pc->insert(m.mk_app(merge, 3, args));
#else
svector<std::pair<unsigned, unsigned> > pos;
vector<expr_ref_vector> substs;
proof* p = src.get_proof();
p = m.mk_hyper_resolve(1, &p, fml, pos, substs);
res->set_proof(m, p);
#endif
}
tgt = res;
}
bool mk_subsumption_checker::transform_rule(rule * r,
rule_subsumption_index& subs_index, rule_ref & res)
{
unsigned u_len = r->get_uninterpreted_tail_size();
unsigned len = r->get_tail_size();
if(u_len==0) {
res = r;
return true;
}
app_ref head(r->get_head(), m);
app_ref_vector tail(m);
svector<bool> tail_neg;
for(unsigned i=0; i<u_len; i++) {
app * tail_atom = r->get_tail(i);
bool neg = r->is_neg_tail(i);
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
//and can be removed
return false;
}
else {
//we remove total relations from the tail
continue;
}
}
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
//can be removed
return false;
}
tail.push_back(tail_atom);
tail_neg.push_back(neg);
}
if(tail.size()==u_len) {
res = r;
return true;
}
//we just copy the interpreted part of the tail
for(unsigned i=u_len; i<len; i++) {
tail.push_back(r->get_tail(i));
tail_neg.push_back(r->is_neg_tail(i));
}
SASSERT(tail.size()==tail_neg.size());
res = m_context.get_rule_manager().mk(head, tail.size(), tail.c_ptr(), tail_neg.c_ptr());
res->set_accounting_parent_object(m_context, r);
m_context.get_rule_manager().fix_unbound_vars(res, true);
m_context.get_rule_manager().mk_rule_rewrite_proof(*r, *res.get());
return true;
}