void contractor_fixpoint::worklist_fixpoint_alg(contractor_status & cs) {
thread_local static queue<unsigned> q;
q = queue<unsigned>(); // empty queue
thread_local static ibex::BitSet ctc_bitset = ibex::BitSet::empty(m_clist.size());
ctc_bitset.clear();
// Add all contractors to the queue.
for (int i = m_clist.size() - 1; i >= 0; --i) {
contractor & c_i = m_clist[i];
contractor_status_guard csg(cs);
c_i.prune(cs);
if (cs.m_box.is_empty()) { return; }
ibex::BitSet const & output_i = cs.m_output;
if (output_i.empty()) {
continue;
}
q.push(i);
ctc_bitset.add(i);
}
if (q.size() == 0) { return; }
// Fixed Point Loop
thread_local static box old_box(cs.m_box);
do {
interruption_point();
old_box = cs.m_box;
unsigned const idx = q.front();
q.pop();
ctc_bitset.remove(idx);
assert(idx < m_clist.size());
contractor & c = m_clist[idx];
contractor_status_guard csg(cs);
c.prune(cs);
if (cs.m_box.is_empty()) {
return;
}
auto const & c_output = cs.m_output;
if (!c_output.empty()) {
// j-th dimension is changed as a result of pruning
// need to add a contractor which takes j-th dim as an input
for (int j = c_output.min(); j <= c_output.max(); ++j) {
if (!c_output.contain(j)) {
continue;
}
for (unsigned k = 0; k < m_clist.size(); ++k) {
// Only add if it's not in the current queue
if (!ctc_bitset.contain(k)) {
contractor const & c_k = m_clist[k];
if (c_k.get_input().contain(j)) {
q.push(k);
ctc_bitset.add(k);
}
}
}
}
}
} while (q.size() > 0 && cs.m_box.max_diam() >= cs.m_config.nra_precision && !m_term_cond(old_box, cs.m_box));
return;
}
void contractor_fixpoint::worklist_fixpoint_alg(contractor_status & cs) {
queue<int> q;
ibex::BitSet ctc_bitset(m_clist.size());
// Add all contractors to the queue.
for (unsigned i = 0; i < m_clist.size(); ++i) {
contractor & c_i = m_clist[i];
contractor_status_guard csg(cs);
c_i.prune(cs);
if (cs.m_box.is_empty()) { return; }
ibex::BitSet const & output_i = cs.m_output;
if (!output_i.empty()) {
assert(!ctc_bitset.contain(i));
q.push(i);
ctc_bitset.add(i);
}
}
if (q.size() == 0) { return; }
// Fixed Point Loop
do {
interruption_point();
unsigned const idx = q.front();
q.pop();
ctc_bitset.remove(idx);
assert(!ctc_bitset.contain(idx));
assert(idx < m_clist.size());
contractor & c = m_clist[idx];
m_old_box = cs.m_box;
contractor_status_guard csg(cs);
c.prune(cs);
if (cs.m_box.is_empty()) { return; }
auto const & c_output = cs.m_output;
if (!c_output.empty()) {
// j-th dimension is changed as a result of pruning
// need to add a contractor which takes j-th dim as an input
int j = c_output.min();
do {
if (!c_output.contain(j)) { continue; }
for (int const dependent_ctc_id : m_dep_map[j]) {
if (!ctc_bitset.contain(dependent_ctc_id)) {
q.push(dependent_ctc_id);
ctc_bitset.add(dependent_ctc_id);
}
}
j = c_output.next(j);
} while (j < c_output.max());
}
} while (q.size() > 0 && (m_old_box != cs.m_box) && cs.m_box.is_bisectable(cs.m_config.nra_precision) && !m_term_cond(m_old_box, cs.m_box));
return;
}
void contractor_cache::prune(contractor_status & cs) {
// extract i-th interval where `m_input[i] == 1`
vector<ibex::Interval> const in = extract_from_box_using_bitset(cs.m_box, m_input);
auto const it = m_cache.find(in);
if (it == m_cache.end()) {
// not found in cache, run m_ctc
++m_num_nohit;
{
contractor_status_guard csg(cs);
assert(cs.m_output.empty());
assert(cs.m_used_constraints.empty());
try {
// run contractor
m_ctc.prune(cs);
// extract out from box.
vector<ibex::Interval> const out = extract_from_box_using_bitset(cs.m_box, cs.m_output);
// save the result to the cache
m_cache.emplace(in, make_tuple(out, cs.m_output, cs.m_used_constraints, false));
} catch (exception & e) {
m_cache.emplace(in, make_tuple(vector<ibex::Interval>(), cs.m_output, cs.m_used_constraints, true));
throw contractor_exception(e.what());
}
}
} else {
++m_num_hit;
// found in cache, use it
auto const & m_cached_content = it->second;
vector<ibex::Interval> const & out = get<0>(m_cached_content);
auto const & output_bitset = get<1>(m_cached_content);
auto const & used_constraints = get<2>(m_cached_content);
bool const was_exception_thrown = get<3>(m_cached_content);
cs.m_used_constraints.insert(used_constraints.begin(), used_constraints.end());
if (was_exception_thrown) {
cs.m_output.union_with(output_bitset);
throw contractor_exception("previously there was an exception in the cached computation");
} else {
// project out to box;
update_box_using_bitset(cs.m_box, out, output_bitset);
cs.m_output.union_with(output_bitset);
}
}
}
