void elim_bounds::operator()(quantifier * q, expr_ref & r) {
if (!q->is_forall()) {
r = q;
return;
}
expr * n = q->get_expr();
ptr_buffer<expr> atoms;
if (m_manager.is_or(n))
atoms.append(to_app(n)->get_num_args(), to_app(n)->get_args());
else
atoms.push_back(n);
used_vars m_used_vars;
// collect non-candidates
unsigned sz = atoms.size();
for (unsigned i = 0; i < sz; i++) {
expr * a = atoms[i];
if (!is_bound(a))
m_used_vars.process(a);
}
if (m_used_vars.uses_all_vars(q->get_num_decls())) {
r = q;
return;
}
// collect candidates
obj_hashtable<var> m_lowers;
obj_hashtable<var> m_uppers;
obj_hashtable<var> m_candidate_set;
ptr_buffer<var> m_candidates;
#define ADD_CANDIDATE(V) if (!m_lowers.contains(V) && !m_uppers.contains(V)) { m_candidate_set.insert(V); m_candidates.push_back(V); }
for (unsigned i = 0; i < sz; i++) {
expr * a = atoms[i];
var * lower = 0;
var * upper = 0;
if (is_bound(a, lower, upper)) {
if (lower != 0 && !m_used_vars.contains(lower->get_idx())) {
ADD_CANDIDATE(lower);
m_lowers.insert(lower);
}
if (upper != 0 && !m_used_vars.contains(upper->get_idx())) {
ADD_CANDIDATE(upper);
m_uppers.insert(upper);
}
}
}
TRACE("elim_bounds", tout << "candidates:\n"; for (unsigned i = 0; i < m_candidates.size(); i++) tout << mk_pp(m_candidates[i], m_manager) << "\n";);
bool elim_bounds_cfg::reduce_quantifier(quantifier * q,
expr * n,
expr * const * new_patterns,
expr * const * new_no_patterns,
expr_ref & result,
proof_ref & result_pr) {
if (!is_forall(q)) {
return false;
}
unsigned num_vars = q->get_num_decls();
ptr_buffer<expr> atoms;
if (m.is_or(n))
atoms.append(to_app(n)->get_num_args(), to_app(n)->get_args());
else
atoms.push_back(n);
used_vars used_vars;
// collect non-candidates
for (expr * a : atoms) {
if (!is_bound(a))
used_vars.process(a);
}
if (used_vars.uses_all_vars(q->get_num_decls())) {
return false;
}
// collect candidates
obj_hashtable<var> lowers;
obj_hashtable<var> uppers;
obj_hashtable<var> candidate_set;
ptr_buffer<var> candidates;
#define ADD_CANDIDATE(V) if (!lowers.contains(V) && !uppers.contains(V)) { candidate_set.insert(V); candidates.push_back(V); }
for (expr * a : atoms) {
var * lower = nullptr;
var * upper = nullptr;
if (is_bound(a, lower, upper)) {
if (lower != nullptr && !used_vars.contains(lower->get_idx()) && lower->get_idx() < num_vars) {
ADD_CANDIDATE(lower);
lowers.insert(lower);
}
if (upper != nullptr && !used_vars.contains(upper->get_idx()) && upper->get_idx() < num_vars) {
ADD_CANDIDATE(upper);
uppers.insert(upper);
}
}
}
TRACE("elim_bounds", tout << "candidates:\n"; for (unsigned i = 0; i < candidates.size(); i++) tout << mk_pp(candidates[i], m) << "\n";);
